Rats! Feb 9, 2009 Published in March 2009 issue of Metchosin Muse
Walking into my laundry room late one night in November, flipping on the light switch and seeing a rat streak up the wall and along the rafters at light speed elicited an immediate and visceral response. The scream I produced would have garnered an Oscar at any horror film awards presentation.
I unwillingly shared my home with this impudent house guest for a number of weeks as it continually foiled my attempts to have it removed, dead or alive.
Most rats in our region are Rattus rattus, also known as black, ship or roof rats. Historically they arrived via ships and because they need a warmer climate than Norway (brown) rats (Rattus norvegicus), they are usually confined to coastal areas, although, if they can find suitable winter habitat (inside your home or business) they can be found in Interior urban areas. They are thought to have originated in India or tropical Asia and are the disseminators of the bubonic plague that killed 30-60% of Europe’s population and many more people from Asia, Africa and India in the fourteenth through eighteenth centuries. Actually the true culprit was the oriental rat flea, which killed the rats as well as the human populations. They have also been implicated in a catastrophic decline in songbird populations when they have been introduced on small islands.
In most of North America, the Norway rat is the one you are most likely to encounter. Where the two rat species co-exist the Norway rats will chose to inhabit basements and the roof rat, the upper levels of buildings. The Norway rat is not from Norway, that is the place they were first scientifically described, it is believed that they originated in northern China.
Mike Kennish of PSI, the pest control specialist that I eventually brought in to deal with “Ratty” has been in the business for eighteen years and the stories he told could curdle your blood or at least cause an involuntary shudder or two. He said that in all those years he has only seen one Norway rat.
Around here, Rattus rattus are commonly known as roof rats because of their preference for aerial habitats. They can run up wallpaper, along wires and rafters and often nest in attics or between floors and ceilings; even in trees and they will burrow under homes in the absence of Norway rats. They are noted for their speed and agility. The stronger, larger Norway rats are infamous for their use of basements, sewers and aquatic areas and for creeping along close to walls, leaving an smeared, oily track. These are the legendary and infamous creatures of New York fame.
Roof rats are territorial and have a rather small home range of no more than 100 m, remaining close to their food source. They are omnivorous but prefer fruits, nuts and grains. Apparently they enjoy snails but it is not recommended to encourage them as a “natural” garden pest solution alternative! Their bodies are fifteen to twenty cm in length, with an equally long, hairless tail and on average, they weigh about 200 grams (1/2 lb). Their fur can show a variety of colours, though northern populations are more likely to be black or steel coloured. Rats are nocturnal animals, if you see them during the day it is because they are so overcrowded the rats lowest in status have been forced to seek food and shelter during the day. Not a good sign!
There is speculation that they have evolved for speed selection. I can attest that these creatures are fast! Ratty sped across my basement rafters in the blink of an eye. Females (does) in heat are chased by groups of males (bucks), with the female selecting the fastest male. The resulting litter of two to eight kittens or pups are born in about twenty-one days and are sexually mature in three months. A healthy female can conceivably reproduce five times a year. Most wild rats live only a year, they have a 91-97% mortality rate, whereas rats in captivity can live three to four years. A group of rats is called a mischief, although the things I have called them are not nearly so whimsical!
Despite the fact that most of us feel a deep sense of revulsion when we even think of rats, they are fascinating animals that are highly evolved survivors.
They haven’t developed particularly acute sight but their long whiskers are used to similarly sense their environment. Their whiskers are extremely sensitive to touch, more so than our fingertips, and research is showing that they are also used in hearing, they can pick up the frequencies produced by brushing against objects. Their whiskers read the world like the blind read Braille, if Braille could be in surroundsound. A rat’s world is a smorgasbord of scent, one percent of their DNA is involved in their sense of smell. This helps them find food and discern its edibility with incredible accuracy. They have a secondary olfactory organ, located in their nose, that is responsible for receiving and relaying chemical signals that often relate to reproduction and social standing. Rats have acute hearing, both for soft sounds and high into the ultrasonic range. We might not be able to hear the sound produced if we rub our finger and thumb together, but rats can.
No matter how much I can respect and admire a rat’s ability to survive and flourish, I still don’t want it in my home. Rats, despite being clean animals themselves (they spend 1/3 of their time grooming), spread disease through their droppings. They use their urine as scent markers and much like the bar codes on our grocery items, each rat’s urine scent is identifiable to other rats. It records their health, sex, reproductive readiness, social standing and a host of other details important to rat life, kind of a rat’s version of Facebook. If conditions are good, all this advertising results in a proliferation of rats and the need to seek out new territory. Rats seek heat, warm and cozy hiding places to raise their young. According to Mike, the best defense against rat intrusions into your home, is to maintain your home in the best condition possible-build to exclude them and keep your garbage at a minimum and securely contained.
Rats do not have the collapsible skeletons that have been attributed to them but an average sized roof rat can squeeze through a hole the size of a quarter. Vines and pipes climbing up the exterior woodwork allow the agile roof rat easy access to any unnoticed openings, into broken vents in soffits or decaying roofs. Inspect the foundation and see if cracks have developed, my rat gained entry through an open door under the steps and then chewed through a 2 x 4 to enlarge a small hole in the concrete foundation, they can chew through concrete too. Check to make sure that all your vents to the outdoors are strong and in place. Second, make sure you are not attracting rats with the delicious aroma of garbage: slightly rotting fruits, well aged meats, seeds and grains. In the spring, rat colonies can be on the move, hungry from the winter’s depredations, looking for more convivial quarters. Don’t hang out an olfactory sign that says Rat Restaurant!
Pet cats and dogs are not always rat deterrents, although I had a standard poodle once that caught a few rats. Terriers and Jack Russells have been bred to be ratters but they need to be trained from an early age. Don’t leave your cat locked in the basement with a rat, sadly, many times the cat will be the loser.
Mike told me in his matter of fact way of storytelling how he had recently been called to a home of a, shall we say, eccentric client. This person had been feeding the neighbourhood squirrels and wildlife to the point they were coming onto the window ledge. By the time he was called in, the neighbourhood was besieged by rats, they were even seen in the trees during the day. In six weeks he captured 335 rats! They had constructed so many burrows under the house that the foundations were no longer structurally sound and the house had to be torn down.
When the inevitable happens and you find a rat in your home, remember you are not alone. Everyone has a rat story. Mike says that most people first hear a rat in the bedroom wall behind their headboard. I remember a saying from my childhood, “If you can hear it, it’s a rat; if you can’t, it’s a mouse!” I tried to catch mine for a week or two but setting the traps was just too heart stopping and I ran out of friends to call to set them for me! Hence my frantic call to Mike. It took a couple of more weeks but eventually Ratty succumbed to the temptation to take the peanut butter bait. I admit I felt a sense of relief when I finally found his body.
The typical extra-large version of a mousetrap is considered the most humane method of dispatching rats and has the least chance of harming your pets. Poisoned baits or the bodies of poisoned rats can be ingested by other non-target animals or the rats can slowly die in the walls of your home. If that has ever happened to you, you know it is not a sensory delight. Rats are phobic about anything new in their environment and they will initially avoid a new trap or food. There are recommendations on baiting but not setting a trap for several days, until the rat has become conditioned to the trap.
Rats and deer mice are known to transmit the Hanta virus through their droppings or the dust from their droppings. Although it has not been recorded from Vancouver Island, to be safe and to prevent breathing in this toxic dust, wear a mask and spray any droppings you find with a ten percent bleach solution, let dry and then vacuum.
Some people keep roof rats as pets; they are said to be clean, intelligent, friendly and playful. Norway rats have a long history as pets and have been bred for the pet and research market. They have been used in studies on heart disease and cancer, in understanding neurological responses and drug reactions. It is somewhat ironic that one of the most reviled animals is also one that has significantly contributed to our understanding of human health.
Along with humans and some primates, new research has shown that rats possess metacognition, the ability to be “aware of their own strengths and weaknesses, the nature of the task at hand, and available "tools" or skills”. No wonder they have conquered the world and survive almost any threats.
Whatever you think of them, rats live among us, following our trails of garbage and discarded foods, seeking our warm shelters. Their intelligence, fecundity and adaptability makes them survivors that require us to use our ingenuity to keep them out of our homes.
2008 was the year of the Rat in Chinese astrology (1925, 1937, 1949, 1961, 1973, 1985, 1997, 2008). People born under this sign are considered honest, generous, creative, curious, hard-working, charismatic, survivors, ambitious, quick tempered, manipulative and selfish. Alexander the Great, Cleopatra and one of my ex-husbands were notable Rats.
References:
http://members.madasafish.com/~cj_whitehound/Rats_Nest/Ship_Rats/Appearance.htm
Gillespie, H. and P. Myers. 2004. "Rattus rattus" (On-line), Animal Diversity Web. Accessed February 09, 2009 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Rattus_rattus.html.
http://en.wikipedia.org/wiki/Black_Rat
Pest Scene Investigations: 250-727-1948
Showing posts with label Invasive Species. Show all posts
Showing posts with label Invasive Species. Show all posts
Friday, February 27, 2009
Monday, October 13, 2008
Spotted Knapweed
Spotted Knapweed and Other Invasive Species
or Out, Damn’d Spot(ted)! Out!
By Moralea Milne Nov 9, 2007
For many of us, fall means innumerable soccer practices and endless hours ferrying our children from one activity to another. For others, cooler weather and shortening days creates the incentive to travel, to seek out warmer and drier climes.
To some of us involved in environmental do-goodism, it is a time for duty. The autumn rains soften the summer baked concrete soils, signaling that it is time to head to Devonian Park or other areas that are rife with invasive species and begin again the Herculean task of rescuing our flora and fauna from the death grip of introduced, invasive species.
Invasive species, alien invaders, dog-gone weeds! Almost more than development and land use changes, they tear at the resolve of environmentalists everywhere. Insidiously they show up, skulking about for years before they seemingly leap out of the blue and claim their territory, decimating meadows, woodlands and wetlands alike. There is an invasive specie for every situation.
Walk through East Sooke Park or parts of Witty’s Lagoon and find the forest floor overrun with that rhodo wannabe, spurge laurel (aka daphne) and that creeping, climbing, suffocating, green menace-English ivy. Meadows that were once clothed in blue camas are now defiantly yellow with broom and gorse. Wetlands throughout the continent have come under ferocious attack by that siren, purple loosestrife, some has recently been spotted in Metchosin. There are bloated bullfrogs, copulating rabbits, raucous flocks of omnipresent starlings and literally millions of proliferating black licorice slugs. There are relatively new weeds like spotted knapweed, tansy ragwort and spartina as well as the older foes like broom, gorse and hedgehog dogtail (grass).
Without too much difficulty you can get me to rant on interminably about introduced, invasive species, no doubt ensuring some eye-rolling and probably causing some people to duck when they see me coming! Why all the furor?
Introduced, invasive species are organisms that have, through no fault of their own, arrived in a new landscape. A landscape that is conducive to their growth and reproductive success and one that does not include any naturally occurring forces that could provide some restraint on their burgeoning populations. Meaning perfect growing conditions and no predators of consequence.
So?
New plants and animals-wouldn’t that add to biodiversity-the buzzword of the times? Unfortunately what happens is that the new organisms, be they of the air, earth or water, act like kids in a candy store. With no natural limits (parents or shopkeeper) they multiply at such a rate that they outcompete the existing flora and fauna (decimate the candy store). They muscle out the highly adapted native species. Instead of a meadow with thousands of plants and dozens of species, you have an impoverished site, a grassland with a only few species and most of these not recognized by the local insects, birds and animals as being edible or supplying habitat values. Adding insult to injury, these newcomers often come equipped with the ability to change their surroundings to be more to their liking. Some release poisons that stop plants from germinating, giving themselves more space to grow; some change the soil components so that there might be more nitrogen, making it harder for plants adapted to poor soils to survive; some use up all available moisture; some, like the introduced grey squirrel, use up the available nesting sites and eat the young of other species.
How do they get here?
They come in a variety of ways. Homesick for the old country? Bring over a few of your favourite species to make you feel more at home in your new landscape, that’s what happened with broom and starlings. Sometimes they arrive inadvertently in a shipment of agricultural seeds (knapweed); sometimes they hitch-hike a ride on a passing ship (rats); or in the ballast water picked up in one port and jettisoned in another (zebra mussels). Sometimes we invite them in, thinking they will take care of a problem (cane toads in Australia or English sparrows which were first imported to help fight agricultural insect pests, although they are primarily grain and seed eaters!) or they come by accident in nursery stock (many pathogens such as Chestnut blight, Dutch elm disease and black licorice slugs). Sometimes the nursery stock itself is to blame, English ivy is used extensively in landscaping and purple loosestrife is a beautiful garden ornamental.
There has been a slight shift in the thinking of those professionals entrusted with the task of designing management strategies to tackle invasive species. While not abandoning the battle to control more established weeds like broom, gorse and ivy, there is now an effort afoot to recognize new invasive plants (and animals!) before they become an entrenched problem. The expectation is that if we can identify and deal with an invasive introduction while it is a relative newcomer, it will be easier to control or even eradicate.
One of our newest invasive species is spotted knapweed. Only a few years ago there were a handful of plants along the road by the gravel pit and at the entrance to Tower Point. Unfortunately no one recognized the danger in time and the large field in the park is now chock-a-bloc full of the weed. If you have ever traveled to the southern interior you will know what a huge problem this can become. There, knapweed is universally hated as it invades pasture and crown land grazing areas, reducing them to knapweed deserts, unfit for livestock or deer and elk. Knapweed is a displaced member of the aster family and one of the plants which secrete a toxin that prevents other plants from growing in the area around them.
At a casual glance it looks somewhat like a smaller variety of thistle and it has a stiff, thistle-like flowerhead, usually purple, with narrow, divided leaves, the layered bracts surrounding the flower are tipped with a triangular black spot-hence its name. Flowering from July till October, it is capable of producing 400 seeds per plant in its normal, dry, growing conditions and up to 25,000 seeds under irrigation! It is a strong competitor on disturbed lands but can also invade natural landscapes.
The most effective and least time consuming way to handle invasive species is to prevent their establishment. Promote healthy native plant communities, disturb soil as little as possible and learn to recognize these alien invaders. Once an infestation is found, a control strategy should be mapped out. Decide where to spend your energy to get the greatest returns. Generally it is recommended to deal with the smallest areas of new invasions on the least disturbed sites, working towards the largest infestations on the most disturbed areas. It is crucial to success to limit new seed production and to deplete the seed bank.
In the case of spotted knapweed, it may be hand pulled, usually three times a year. Once, while the soil is still moist and pulling can remove the taproot; secondly, after the remaining plants have bolted (they form ground hugging rosettes-somewhat resembling dock- that will send up a flowering stalk)-usually in late June; and thirdly before seeds are dispersed. Mowing and cutting can be somewhat effective and should be carried out in the early flower stage; plants are less likely to resprout if allowed to bolt before cutting. Cutting must be repeated over several years to deplete the seedbank. If you are interested in using a chemical solution, non-selective herbicides will need repeat applications (a wipe-on application of Round-up is recommended) but first consult an accredited professional for advice. New plants will germinate, so remember to keep visiting the site and remove of any newly emerging or resprouting plants.
Other new invasive plant species are: carpet burweed, orange hawkweed, giant and Japanese knotweeds, dalmation toadflax, yellow flag iris, giant hogweed and butterfly weed. Contact the Coastal Invasive Plant Committee for more information at info@coastalinvasiveplants.com or 857-4272.
Too numerous and too successful and sometimes it seems, on a particularly disheartening day, too impossible to even contemplate controlling. However, some Sunday mornings during the winter months, we manage to have some fun and share good times at Devonian Regional Park as we continue our “duty” at the park. It will be seven years this season that we have been involved in removing broom from the park and we are making a difference. If you would like to join us, contact Moralea at 478-3838 or moralea@telus.net.
or Out, Damn’d Spot(ted)! Out!
By Moralea Milne Nov 9, 2007
For many of us, fall means innumerable soccer practices and endless hours ferrying our children from one activity to another. For others, cooler weather and shortening days creates the incentive to travel, to seek out warmer and drier climes.
To some of us involved in environmental do-goodism, it is a time for duty. The autumn rains soften the summer baked concrete soils, signaling that it is time to head to Devonian Park or other areas that are rife with invasive species and begin again the Herculean task of rescuing our flora and fauna from the death grip of introduced, invasive species.
Invasive species, alien invaders, dog-gone weeds! Almost more than development and land use changes, they tear at the resolve of environmentalists everywhere. Insidiously they show up, skulking about for years before they seemingly leap out of the blue and claim their territory, decimating meadows, woodlands and wetlands alike. There is an invasive specie for every situation.
Walk through East Sooke Park or parts of Witty’s Lagoon and find the forest floor overrun with that rhodo wannabe, spurge laurel (aka daphne) and that creeping, climbing, suffocating, green menace-English ivy. Meadows that were once clothed in blue camas are now defiantly yellow with broom and gorse. Wetlands throughout the continent have come under ferocious attack by that siren, purple loosestrife, some has recently been spotted in Metchosin. There are bloated bullfrogs, copulating rabbits, raucous flocks of omnipresent starlings and literally millions of proliferating black licorice slugs. There are relatively new weeds like spotted knapweed, tansy ragwort and spartina as well as the older foes like broom, gorse and hedgehog dogtail (grass).
Without too much difficulty you can get me to rant on interminably about introduced, invasive species, no doubt ensuring some eye-rolling and probably causing some people to duck when they see me coming! Why all the furor?
Introduced, invasive species are organisms that have, through no fault of their own, arrived in a new landscape. A landscape that is conducive to their growth and reproductive success and one that does not include any naturally occurring forces that could provide some restraint on their burgeoning populations. Meaning perfect growing conditions and no predators of consequence.
So?
New plants and animals-wouldn’t that add to biodiversity-the buzzword of the times? Unfortunately what happens is that the new organisms, be they of the air, earth or water, act like kids in a candy store. With no natural limits (parents or shopkeeper) they multiply at such a rate that they outcompete the existing flora and fauna (decimate the candy store). They muscle out the highly adapted native species. Instead of a meadow with thousands of plants and dozens of species, you have an impoverished site, a grassland with a only few species and most of these not recognized by the local insects, birds and animals as being edible or supplying habitat values. Adding insult to injury, these newcomers often come equipped with the ability to change their surroundings to be more to their liking. Some release poisons that stop plants from germinating, giving themselves more space to grow; some change the soil components so that there might be more nitrogen, making it harder for plants adapted to poor soils to survive; some use up all available moisture; some, like the introduced grey squirrel, use up the available nesting sites and eat the young of other species.
How do they get here?
They come in a variety of ways. Homesick for the old country? Bring over a few of your favourite species to make you feel more at home in your new landscape, that’s what happened with broom and starlings. Sometimes they arrive inadvertently in a shipment of agricultural seeds (knapweed); sometimes they hitch-hike a ride on a passing ship (rats); or in the ballast water picked up in one port and jettisoned in another (zebra mussels). Sometimes we invite them in, thinking they will take care of a problem (cane toads in Australia or English sparrows which were first imported to help fight agricultural insect pests, although they are primarily grain and seed eaters!) or they come by accident in nursery stock (many pathogens such as Chestnut blight, Dutch elm disease and black licorice slugs). Sometimes the nursery stock itself is to blame, English ivy is used extensively in landscaping and purple loosestrife is a beautiful garden ornamental.
There has been a slight shift in the thinking of those professionals entrusted with the task of designing management strategies to tackle invasive species. While not abandoning the battle to control more established weeds like broom, gorse and ivy, there is now an effort afoot to recognize new invasive plants (and animals!) before they become an entrenched problem. The expectation is that if we can identify and deal with an invasive introduction while it is a relative newcomer, it will be easier to control or even eradicate.
One of our newest invasive species is spotted knapweed. Only a few years ago there were a handful of plants along the road by the gravel pit and at the entrance to Tower Point. Unfortunately no one recognized the danger in time and the large field in the park is now chock-a-bloc full of the weed. If you have ever traveled to the southern interior you will know what a huge problem this can become. There, knapweed is universally hated as it invades pasture and crown land grazing areas, reducing them to knapweed deserts, unfit for livestock or deer and elk. Knapweed is a displaced member of the aster family and one of the plants which secrete a toxin that prevents other plants from growing in the area around them.
At a casual glance it looks somewhat like a smaller variety of thistle and it has a stiff, thistle-like flowerhead, usually purple, with narrow, divided leaves, the layered bracts surrounding the flower are tipped with a triangular black spot-hence its name. Flowering from July till October, it is capable of producing 400 seeds per plant in its normal, dry, growing conditions and up to 25,000 seeds under irrigation! It is a strong competitor on disturbed lands but can also invade natural landscapes.
The most effective and least time consuming way to handle invasive species is to prevent their establishment. Promote healthy native plant communities, disturb soil as little as possible and learn to recognize these alien invaders. Once an infestation is found, a control strategy should be mapped out. Decide where to spend your energy to get the greatest returns. Generally it is recommended to deal with the smallest areas of new invasions on the least disturbed sites, working towards the largest infestations on the most disturbed areas. It is crucial to success to limit new seed production and to deplete the seed bank.
In the case of spotted knapweed, it may be hand pulled, usually three times a year. Once, while the soil is still moist and pulling can remove the taproot; secondly, after the remaining plants have bolted (they form ground hugging rosettes-somewhat resembling dock- that will send up a flowering stalk)-usually in late June; and thirdly before seeds are dispersed. Mowing and cutting can be somewhat effective and should be carried out in the early flower stage; plants are less likely to resprout if allowed to bolt before cutting. Cutting must be repeated over several years to deplete the seedbank. If you are interested in using a chemical solution, non-selective herbicides will need repeat applications (a wipe-on application of Round-up is recommended) but first consult an accredited professional for advice. New plants will germinate, so remember to keep visiting the site and remove of any newly emerging or resprouting plants.
Other new invasive plant species are: carpet burweed, orange hawkweed, giant and Japanese knotweeds, dalmation toadflax, yellow flag iris, giant hogweed and butterfly weed. Contact the Coastal Invasive Plant Committee for more information at info@coastalinvasiveplants.com or 857-4272.
Too numerous and too successful and sometimes it seems, on a particularly disheartening day, too impossible to even contemplate controlling. However, some Sunday mornings during the winter months, we manage to have some fun and share good times at Devonian Regional Park as we continue our “duty” at the park. It will be seven years this season that we have been involved in removing broom from the park and we are making a difference. If you would like to join us, contact Moralea at 478-3838 or moralea@telus.net.
Sunday, October 12, 2008
Broom and Gorse
Dastardly Duo Destroy Habitat, Imperil Homes
Jan 29, 2004
Once again it is the season when the hedgerows and roadsides begin to bloom with the bright yellow, pea-like flowers of gorse and broom. Like after dinner guests who just won’t leave, many people are finding these harbingers of spring have outstayed their welcome. Unfortunately, after we invited them to our shores and even carefully tended to their initial shaky start, they have flourished and exhibited their “no holds barred” strategies for survival.
These highly adaptable and successful invasive plants have many tactics to ensure their continuation. Like those people fortunate enough to have a healthy bank account that can take them through retirement, broom and gorse ensure their long term existence with a sizable seedbank. They produce copious quantities of seeds that remain viable in the soil for many, many years (some accounts have broom seeds still able to germinate after 80 years!). The determined work of homeowners and volunteers to remove these plants is made more challenging by the continued germination or “withdrawals” from the seedbank. One of the challenges of removing broom and gorse plants is that the light that now reaches the ground will often stimulate the seedbank to sprout.
Another weapon in their arsenal of survival strategies is the ability to resprout. In my experience, the two species are not created equal. Broom is much more likely to die if cut to the ground, while gorse usually surges back, virtually none the worse for its pruning. This makes gorse, in particular, very difficult to control. For all that many of us think of broom as a terrible pest, gorse is its nasty, brutish cousin. Infested with long sharp spines, it seems determined to inflict as much damage as possible on anyone who attempts to control its spread. One publication states that “a single (gorse) plant can be 10 m in diameter”. So first you must whack you way through 5 m of fierce spiny branches to get to the main trunk and then you cut it back, only to have it resprout soon after!
Both gorse and broom belong to the pea family, plants that change soil chemistry by adding nitrogen through their root structures. While enhancing the soil with nitrogen is something we all think is a great thing for our flower and vegetable gardens, it can have a very negative effect on our native plants. Also, the litter they drop, in the form of leaves and branches, changes the soil by making it more acid.
In all natural plant communities, there are plants, who, like the kids at school who were smart, athletic and popular, have it all. They can survive and flourish in diverse situations, while others, sort of like the kids in the computer club, are able to find their niche in places too dry, too wet or too poor for the more generalist species. When introduced, invasive plants; such as broom and gorse, arrive and enrich and acidify the soil, they change the soil dynamics and the more sensitive, specialized plants are crowded out (goodbye computer club). As you can see from this analogy, it is important to help retain our native species and the ecosystems they inhabit. It’s more than possible they have something valuable to contribute, just as the archtypical computer nerd, Bill Gates, contributes substantial benefits to our communities.
Besides the loss of native species and biodiversity that broom and gorse engender, they are extremely dangerous fire hazards. Both species are full of volatile oils that produce hotter than normal fires. Gorse in particular, is a fire waiting to happen. It contains more oils than broom and as it grows, the inner branches die off and become dense, highly flammable dead material just waiting for a cigarette, carelessly thrown from a passing car window, to ignite it. Remember how nervous we all were last summer throughout fire season? I would wager that cigarette buts being tossed into stands of gorse and broom is high on the list of our fire chief's nightmare scenarios. Even if you don’t understand all the fuss about protecting the native environment, you should be worried about the proliferation of broom and gorse and their destructive potential to your home and family from their extreme flammability.
Methods to Control Broom and Gorse
In the best of all possible worlds, there is the most advantageous time to do things. However, real life often interferes with those schedules and best intentions. It is better to tackle invasive species when you can, rather than wait for the “right” time and miss it because you are busy or distracted by something else. I have had a lot of success cutting broom in the wet season, provided it is cut to or just below soil level. A stub, however, especially on young plants, will often regrow, although “old growth” broom is less prone to resrouting. If you are removing plants from roadsides with ditches during the wet season, take care not to let any dirt fall into the water. We don’t want to remove the invasive plants only to endanger aquatic habitat!
Always start with areas which have the fewest invasive plants and work towards areas with the highest densities. If you have an area with only a couple of broom or gorse plants, take them out first, to remove their ability to flower and build up the seedbank. Face it, in densely invaded areas the seedbank is already well endowed! Aside from roadways; work from areas of greatest sensitivity to areas of most disturbance. For example; work first from areas with the highest density of native and rare plants, to areas of stripped hillsides. That said:
➢ Cut plants to the ground just after flowering when much of the plant's energy has been depleted but before seed set, or during the summer, when the plant will already be stressed from our summer droughts.
➢ Small plants can be easily pulled in the winter, when the soil is thoroughly wet, although this can cause soil disturbance, which can encourage seed germination. It can also dislodge any native bulbs that might still be surviving. I generally place my boots against the plant as I pull, to minimize disturbance. This is particularly important on rocky moss balds, with their shallow soils.
➢ To deal with the more problematic gorse, I have read articles that endorse the “cut and paint” method. This entails cutting the gorse to ground level and then “painting” the stump and any remaining bark with a systemic herbicide such as Round-up™ at one part Round-up ™to 5 parts water (200ml Round-up™/litre water). There is conflicting advice on the amount of time that you have, (from 20 seconds to 20 minutes) from making the cut to applying the solution. It is more likely to be successful if done either in late spring or in the fall when roots are regrowing. You can apply with a squeeze bottle, using protective gear. Before applying, speak to a certified pesticide specialist and use all precautions recommended.
➢ Herbicides have apparently been successful with younger plants but must be used with extreme caution. Contact an certified pesticide expert.
➢ Repeated burning has been recommended as a way to kill off small plants that germinate once the seedbank has been stimulated. To reduce risk of forest fires, try a tiger torch in the wet season, but be careful not to damage native plants and the mosses and lichens that protect the soil. This is experimental only and expert advice should be obtained first.
➢ There has been some success with covering the newly broom and gorse free soil with back plastic to kill off the seedlings, however this will substantially damage any native vegetation. Replant with appropriate native plants.
➢ The Bradley Method entails removing invasive species from areas around native plants and slowly, as the natives gain strength and dominance, venture further into the infestation. This is a long term tactic that has been successfully used in New Zealand.
➢ Treating pastures with lime, to raise the pH, has been partly successful, either by weakening the gorse and broom or by increased competition from other plants more adapted to increased pH levels.
All of these methods are only effective if there is a commitment to continue removing broom and gorse for a very long time. There is no easy panacea for the problems they pose. Although gorse is becoming prevelent in Metchosin, East Sooke and Langford, as yet it has only a toehold on Southern Vancouver Island. If we work now to eradicate it, we might prevent the type of severe infestation that has destroyed great swaths of New Zealand, Hawaii and other countries.
References:
Garry Oak Ecosystems Recovery Team, 2003. Invasive Species in Garry Oak and Associated Ecosystems in British Columbia. Garry Oak Ecosystems Recovery Team, Victoria, BC. Website: http://www.goert.ca/reference/invspecies.htm
Hoshovsky, M., 2001. Element Stewardship Abstract for Ulex Europaeus. The Nature Conservancy, Arlington, Virginia. From the website: http://www.conserveonline.org/2001/05/d/en/ulexeur.PDF
Mallinson, R, 1998. Pest Plant Control, Gorse Fact Sheet PP05/98, Whakatane, New Zealand. From the website: http://www.ebop.govt.nz/Land/Plants/Fact-Sheets.asp
Jan 29, 2004
Once again it is the season when the hedgerows and roadsides begin to bloom with the bright yellow, pea-like flowers of gorse and broom. Like after dinner guests who just won’t leave, many people are finding these harbingers of spring have outstayed their welcome. Unfortunately, after we invited them to our shores and even carefully tended to their initial shaky start, they have flourished and exhibited their “no holds barred” strategies for survival.
These highly adaptable and successful invasive plants have many tactics to ensure their continuation. Like those people fortunate enough to have a healthy bank account that can take them through retirement, broom and gorse ensure their long term existence with a sizable seedbank. They produce copious quantities of seeds that remain viable in the soil for many, many years (some accounts have broom seeds still able to germinate after 80 years!). The determined work of homeowners and volunteers to remove these plants is made more challenging by the continued germination or “withdrawals” from the seedbank. One of the challenges of removing broom and gorse plants is that the light that now reaches the ground will often stimulate the seedbank to sprout.
Another weapon in their arsenal of survival strategies is the ability to resprout. In my experience, the two species are not created equal. Broom is much more likely to die if cut to the ground, while gorse usually surges back, virtually none the worse for its pruning. This makes gorse, in particular, very difficult to control. For all that many of us think of broom as a terrible pest, gorse is its nasty, brutish cousin. Infested with long sharp spines, it seems determined to inflict as much damage as possible on anyone who attempts to control its spread. One publication states that “a single (gorse) plant can be 10 m in diameter”. So first you must whack you way through 5 m of fierce spiny branches to get to the main trunk and then you cut it back, only to have it resprout soon after!
Both gorse and broom belong to the pea family, plants that change soil chemistry by adding nitrogen through their root structures. While enhancing the soil with nitrogen is something we all think is a great thing for our flower and vegetable gardens, it can have a very negative effect on our native plants. Also, the litter they drop, in the form of leaves and branches, changes the soil by making it more acid.
In all natural plant communities, there are plants, who, like the kids at school who were smart, athletic and popular, have it all. They can survive and flourish in diverse situations, while others, sort of like the kids in the computer club, are able to find their niche in places too dry, too wet or too poor for the more generalist species. When introduced, invasive plants; such as broom and gorse, arrive and enrich and acidify the soil, they change the soil dynamics and the more sensitive, specialized plants are crowded out (goodbye computer club). As you can see from this analogy, it is important to help retain our native species and the ecosystems they inhabit. It’s more than possible they have something valuable to contribute, just as the archtypical computer nerd, Bill Gates, contributes substantial benefits to our communities.
Besides the loss of native species and biodiversity that broom and gorse engender, they are extremely dangerous fire hazards. Both species are full of volatile oils that produce hotter than normal fires. Gorse in particular, is a fire waiting to happen. It contains more oils than broom and as it grows, the inner branches die off and become dense, highly flammable dead material just waiting for a cigarette, carelessly thrown from a passing car window, to ignite it. Remember how nervous we all were last summer throughout fire season? I would wager that cigarette buts being tossed into stands of gorse and broom is high on the list of our fire chief's nightmare scenarios. Even if you don’t understand all the fuss about protecting the native environment, you should be worried about the proliferation of broom and gorse and their destructive potential to your home and family from their extreme flammability.
Methods to Control Broom and Gorse
In the best of all possible worlds, there is the most advantageous time to do things. However, real life often interferes with those schedules and best intentions. It is better to tackle invasive species when you can, rather than wait for the “right” time and miss it because you are busy or distracted by something else. I have had a lot of success cutting broom in the wet season, provided it is cut to or just below soil level. A stub, however, especially on young plants, will often regrow, although “old growth” broom is less prone to resrouting. If you are removing plants from roadsides with ditches during the wet season, take care not to let any dirt fall into the water. We don’t want to remove the invasive plants only to endanger aquatic habitat!
Always start with areas which have the fewest invasive plants and work towards areas with the highest densities. If you have an area with only a couple of broom or gorse plants, take them out first, to remove their ability to flower and build up the seedbank. Face it, in densely invaded areas the seedbank is already well endowed! Aside from roadways; work from areas of greatest sensitivity to areas of most disturbance. For example; work first from areas with the highest density of native and rare plants, to areas of stripped hillsides. That said:
➢ Cut plants to the ground just after flowering when much of the plant's energy has been depleted but before seed set, or during the summer, when the plant will already be stressed from our summer droughts.
➢ Small plants can be easily pulled in the winter, when the soil is thoroughly wet, although this can cause soil disturbance, which can encourage seed germination. It can also dislodge any native bulbs that might still be surviving. I generally place my boots against the plant as I pull, to minimize disturbance. This is particularly important on rocky moss balds, with their shallow soils.
➢ To deal with the more problematic gorse, I have read articles that endorse the “cut and paint” method. This entails cutting the gorse to ground level and then “painting” the stump and any remaining bark with a systemic herbicide such as Round-up™ at one part Round-up ™to 5 parts water (200ml Round-up™/litre water). There is conflicting advice on the amount of time that you have, (from 20 seconds to 20 minutes) from making the cut to applying the solution. It is more likely to be successful if done either in late spring or in the fall when roots are regrowing. You can apply with a squeeze bottle, using protective gear. Before applying, speak to a certified pesticide specialist and use all precautions recommended.
➢ Herbicides have apparently been successful with younger plants but must be used with extreme caution. Contact an certified pesticide expert.
➢ Repeated burning has been recommended as a way to kill off small plants that germinate once the seedbank has been stimulated. To reduce risk of forest fires, try a tiger torch in the wet season, but be careful not to damage native plants and the mosses and lichens that protect the soil. This is experimental only and expert advice should be obtained first.
➢ There has been some success with covering the newly broom and gorse free soil with back plastic to kill off the seedlings, however this will substantially damage any native vegetation. Replant with appropriate native plants.
➢ The Bradley Method entails removing invasive species from areas around native plants and slowly, as the natives gain strength and dominance, venture further into the infestation. This is a long term tactic that has been successfully used in New Zealand.
➢ Treating pastures with lime, to raise the pH, has been partly successful, either by weakening the gorse and broom or by increased competition from other plants more adapted to increased pH levels.
All of these methods are only effective if there is a commitment to continue removing broom and gorse for a very long time. There is no easy panacea for the problems they pose. Although gorse is becoming prevelent in Metchosin, East Sooke and Langford, as yet it has only a toehold on Southern Vancouver Island. If we work now to eradicate it, we might prevent the type of severe infestation that has destroyed great swaths of New Zealand, Hawaii and other countries.
References:
Garry Oak Ecosystems Recovery Team, 2003. Invasive Species in Garry Oak and Associated Ecosystems in British Columbia. Garry Oak Ecosystems Recovery Team, Victoria, BC. Website: http://www.goert.ca/reference/invspecies.htm
Hoshovsky, M., 2001. Element Stewardship Abstract for Ulex Europaeus. The Nature Conservancy, Arlington, Virginia. From the website: http://www.conserveonline.org/2001/05/d/en/ulexeur.PDF
Mallinson, R, 1998. Pest Plant Control, Gorse Fact Sheet PP05/98, Whakatane, New Zealand. From the website: http://www.ebop.govt.nz/Land/Plants/Fact-Sheets.asp
Bullfrogs "Tastes Like Chicken"
TASTES LIKE CHICKEN!
What tastes like chicken, is as large as a (small Bantam) chicken and eats ducklings?
Metchosin’s newest unwanted residents are giant bullfrogs that can be eight inches in length, weigh a pound and a half, have a loud, deep, sonorous call that is somewhat like a stuttering foghorn and ravenous appetites which are only controlled by what will fit in their ample mouths. Insects, snakes, birds, salamanders, fish, native frogs, even their own young are fair game for these frog leviathans.
Unfortunately, sometime in the 1930’s bullfrogs were introduced to Vancouver Island by entrepreneurial spirits who hoped to farm them for their small, chicken-like drumsticks (why not chickens you might ask). However the reality is that it takes a minimum of three years (usually more), under ideal circumstances, to grow a marketable frog and they are difficult to feed. Although they will eat almost anything, it must be moving prey and supplying sufficient quantities of live feed is expensive. So, plans that started out with high expectations were not realized and many frogs were dumped into our local lakes and ponds to fend for themselves.
It took awhile (apparently many invasive species spend 40-80 years slowly enlarging their range before they exhibit exploding populations) but bullfrogs have become the newest in a long line of introduced, invasive species to call Metchosin home.
And what is so bad about that?
Lots!
They eat too many of our native species that have not evolved methods to evade them. Our red-legged frogs are in decline and are included in the province’s blue list; they don't need this extra burden on their chances for survival. Bullfrogs are also thought to transmit but not be affected by the potentially fatal frog disease Bd or chytrid fungus that has caused mass mortalities of some amphibians species around the world, the impact on amphibians on Vancouver Island is not known yet. Bd is amphibian specific and will not harm humans, ducks or fish.
They have few predators here because our native species that could hunt them have not evolved to eat them and just don’t recognize the food opportunity that bullfrogs present. Bullfrogs are cannibalistic and they are their own most fearsome predators As well, bullfrogs have protected themselves for eons by producing eggs and tadpoles that are considered distasteful to many would-be predators.
Bullfrogs adapt easily to disturbed habitats. Because they need 20-25ºc water temperatures before they can breed in June/July, they like the increase in water temperature that comes when riparian vegetation is removed and the sun can beat down on open water. Because their tadpoles take one to two years until they transform into frogs, they need bodies of permanent water. When we change a temporary wetland into a year round pond or even construct ponds, we are sending out an invitation to bullfrogs that reads, “Highly desirable accommodations with excellent food supply available for newcomers!”
Our native red-legged frogs and Pacific treefrogs breed in early spring in temporary (and permanent) wetlands that can dry up by mid-summer. However this type of habitat is increasingly scarce as development and ignorance of their importance cause them to be bulldozed and paved or converted into year round ponds. This in turns leads to increased proximity with these new arrivals as bullfrogs and our native amphibians use the remaining lakes and ponds.
Adult bullfrogs are easy to recognize because of their large size, smooth skin (not warty like our toads), round disk on the side of their heads (set near their eyes), and their guttural vocal displays. They are somewhat more problematic to recognize in their younger stages. A young bullfrog might be confused with an adult red-legged frog but a bullfrog has the large ear drums and a red-legged frog has reddish colouring on the inside of its thigh.
Our native frogs breed in early spring and the raucous two-note chorus you hear early in the year is from our treefrogs. Red-legged frogs only call underwater and western toads have a quiet twittering bird-like vocalization. Bullfrogs remain hibernating on lake bottoms until late April or early May and their mating calls happen from May through August. One story has it that they are named bullfrogs because their calls “sound like a bull a quarter mile off”!
Bullfrog egg masses can be found for only a few days after mating, during the summer, and they look like poppy seeds scattered in a large (1 m x 1 m) patch of frothy slime which may be covered in algae. No wonder they are proliferating, they can contain up to 20,000 eggs! If you find an egg mass like this, often surrounded by vegetation, try to gently lift it out of the water (it breaks apart easily) or suck it out with your shop vac or bilge pump! However do not attempt this unless you are have a positive identification that you are looking at bullfrog spawn. Get expert advice.
Our other aquatic amphibians have dissimilar egg masses that you should be able to differentiate. Treefrog and red-legged frog egg masses are found earlier in the year; treefrogs are only about 4 cm in size and round with 12-60 eggs while red-legged frog egg masses are cantaloupe sized. In mid-spring, western toads lay long single strands of eggs, although many strands may be laid on top of one another.
Our aquatic salamanders all have distinctive eggs that cannot be confused with the bullfrogs. Northwest salamanders eggs are massed into a firm orange to grapefruit sized ball of jelly, long-toed salamanders are laid singly or in small plum sized masses that are attached to rocks or vegetation and roughskin newts hide their single eggs so they are difficult to find.
The best way to protect our native species and to prevent the influx of bullfrogs is to refrain from moving frogs, their eggs or tadpoles. If you have a new pond that you would like populated by our native frogs and salamanders, supply conditions they can use and they will find you, they are always on the hunt for new habitat. There is a provincial law which prohibits the release or transport of non-native species except by permit and in 1992 the federal government signed onto the Convention on Biological Diversity which reads “as far as possible and as appropriate, prevent the introduction of, control or eradicate those alien species which threaten ecosystems, habitat or species”. It seems highly unlikely anyone will get even a token fine for being in contravention of these laws but your good conscience might dissuade you.
Additional ways to prevent bullfrog infestations include retaining your seasonal wetlands and resisting the temptation to turn them into permanent waterbodies. Try to leave the shoreline vegetation intact or replant with native species, which helps to keep water temperatures cooler and undesirable to bullfrogs. Even where bullfrogs are numerous some native species can survive if there is enough vegetation that can provide protected areas in which to hide and feed.
Bullfrog tadpoles start small but can reach up to six inches in length and have been used as fish bait. Sometimes the bait swims away and starts to colonise new areas so please resist using them as bait.
If you would like to capture the adults, they are most easily approached at night, quietly and slowly, using a bright light which will immobilize them for a while. There are many methods of capture including using nets, spears, bows and arrows and angling. Use weapons only for adult bullfrogs so that there is no confusion between the juvenile bullfrogs and red-legged frogs. The animal care community has approved any method which rapidly severs brain function, such as decapitation. According to an article I recently read “the most humane way to kill the cold-blooded bullfrogs is to place them in a sealed container in the refrigerator for about 6-12 hours to kick in their hibernation instincts, and then place them in a freezer for one-two days.”. I’m not sure how the rest of the family will react to a fridge full of frogs however! Cajun frog legs?
Broom, gorse, tansy ragwort, rabbits, starlings and now bullfrogs; all these invasive species are having a huge impact on our natural ecosystems. However bullfrogs have just arrived in Metchosin and perhaps with a little knowledge and persistence we can contain or eradicate them before they cause irreparable damage. For more information, contact the Bullfrog Project or Bullfrog Control, listed below.
References:
Amphibians of Oregon, Washington and British Columbia by Corkran and Thoms
The Bullfrog Project: http://web.uvic.ca/bullfrogs
Bullfrog Control: http://64.246.185.201
Cajun Frog Legs Recipe from the Internet:
Ingredients: 16 good sized frog legs, 1 cup shortening, 1/2 cup flour, 3 cups milk, 1 tsp paprika. 1/2 tsp onion powder, 1/2 tsp garlic juice, 1/2 tsp ground cayenne pepper, 1/4 tsp black pepper, 1 dash white pepper, 1 dash oregano, 1 dash rosemary, salt to taste
Directions: Skin, clean and rinse frog legs well. Cover with whole milk and garlic juice in a plastic mixing bowl, refrigerate overnight. Pat dry, season with paprika, onion powder, cayenne, black pepper and desired amount of salt. Add white pepper, oregano and rosemary to the flour. Heat shortening in a skillet. Lightly flour the frog legs and fry until golden brown.
What tastes like chicken, is as large as a (small Bantam) chicken and eats ducklings?
Metchosin’s newest unwanted residents are giant bullfrogs that can be eight inches in length, weigh a pound and a half, have a loud, deep, sonorous call that is somewhat like a stuttering foghorn and ravenous appetites which are only controlled by what will fit in their ample mouths. Insects, snakes, birds, salamanders, fish, native frogs, even their own young are fair game for these frog leviathans.
Unfortunately, sometime in the 1930’s bullfrogs were introduced to Vancouver Island by entrepreneurial spirits who hoped to farm them for their small, chicken-like drumsticks (why not chickens you might ask). However the reality is that it takes a minimum of three years (usually more), under ideal circumstances, to grow a marketable frog and they are difficult to feed. Although they will eat almost anything, it must be moving prey and supplying sufficient quantities of live feed is expensive. So, plans that started out with high expectations were not realized and many frogs were dumped into our local lakes and ponds to fend for themselves.
It took awhile (apparently many invasive species spend 40-80 years slowly enlarging their range before they exhibit exploding populations) but bullfrogs have become the newest in a long line of introduced, invasive species to call Metchosin home.
And what is so bad about that?
Lots!
They eat too many of our native species that have not evolved methods to evade them. Our red-legged frogs are in decline and are included in the province’s blue list; they don't need this extra burden on their chances for survival. Bullfrogs are also thought to transmit but not be affected by the potentially fatal frog disease Bd or chytrid fungus that has caused mass mortalities of some amphibians species around the world, the impact on amphibians on Vancouver Island is not known yet. Bd is amphibian specific and will not harm humans, ducks or fish.
They have few predators here because our native species that could hunt them have not evolved to eat them and just don’t recognize the food opportunity that bullfrogs present. Bullfrogs are cannibalistic and they are their own most fearsome predators As well, bullfrogs have protected themselves for eons by producing eggs and tadpoles that are considered distasteful to many would-be predators.
Bullfrogs adapt easily to disturbed habitats. Because they need 20-25ºc water temperatures before they can breed in June/July, they like the increase in water temperature that comes when riparian vegetation is removed and the sun can beat down on open water. Because their tadpoles take one to two years until they transform into frogs, they need bodies of permanent water. When we change a temporary wetland into a year round pond or even construct ponds, we are sending out an invitation to bullfrogs that reads, “Highly desirable accommodations with excellent food supply available for newcomers!”
Our native red-legged frogs and Pacific treefrogs breed in early spring in temporary (and permanent) wetlands that can dry up by mid-summer. However this type of habitat is increasingly scarce as development and ignorance of their importance cause them to be bulldozed and paved or converted into year round ponds. This in turns leads to increased proximity with these new arrivals as bullfrogs and our native amphibians use the remaining lakes and ponds.
Adult bullfrogs are easy to recognize because of their large size, smooth skin (not warty like our toads), round disk on the side of their heads (set near their eyes), and their guttural vocal displays. They are somewhat more problematic to recognize in their younger stages. A young bullfrog might be confused with an adult red-legged frog but a bullfrog has the large ear drums and a red-legged frog has reddish colouring on the inside of its thigh.
Our native frogs breed in early spring and the raucous two-note chorus you hear early in the year is from our treefrogs. Red-legged frogs only call underwater and western toads have a quiet twittering bird-like vocalization. Bullfrogs remain hibernating on lake bottoms until late April or early May and their mating calls happen from May through August. One story has it that they are named bullfrogs because their calls “sound like a bull a quarter mile off”!
Bullfrog egg masses can be found for only a few days after mating, during the summer, and they look like poppy seeds scattered in a large (1 m x 1 m) patch of frothy slime which may be covered in algae. No wonder they are proliferating, they can contain up to 20,000 eggs! If you find an egg mass like this, often surrounded by vegetation, try to gently lift it out of the water (it breaks apart easily) or suck it out with your shop vac or bilge pump! However do not attempt this unless you are have a positive identification that you are looking at bullfrog spawn. Get expert advice.
Our other aquatic amphibians have dissimilar egg masses that you should be able to differentiate. Treefrog and red-legged frog egg masses are found earlier in the year; treefrogs are only about 4 cm in size and round with 12-60 eggs while red-legged frog egg masses are cantaloupe sized. In mid-spring, western toads lay long single strands of eggs, although many strands may be laid on top of one another.
Our aquatic salamanders all have distinctive eggs that cannot be confused with the bullfrogs. Northwest salamanders eggs are massed into a firm orange to grapefruit sized ball of jelly, long-toed salamanders are laid singly or in small plum sized masses that are attached to rocks or vegetation and roughskin newts hide their single eggs so they are difficult to find.
The best way to protect our native species and to prevent the influx of bullfrogs is to refrain from moving frogs, their eggs or tadpoles. If you have a new pond that you would like populated by our native frogs and salamanders, supply conditions they can use and they will find you, they are always on the hunt for new habitat. There is a provincial law which prohibits the release or transport of non-native species except by permit and in 1992 the federal government signed onto the Convention on Biological Diversity which reads “as far as possible and as appropriate, prevent the introduction of, control or eradicate those alien species which threaten ecosystems, habitat or species”. It seems highly unlikely anyone will get even a token fine for being in contravention of these laws but your good conscience might dissuade you.
Additional ways to prevent bullfrog infestations include retaining your seasonal wetlands and resisting the temptation to turn them into permanent waterbodies. Try to leave the shoreline vegetation intact or replant with native species, which helps to keep water temperatures cooler and undesirable to bullfrogs. Even where bullfrogs are numerous some native species can survive if there is enough vegetation that can provide protected areas in which to hide and feed.
Bullfrog tadpoles start small but can reach up to six inches in length and have been used as fish bait. Sometimes the bait swims away and starts to colonise new areas so please resist using them as bait.
If you would like to capture the adults, they are most easily approached at night, quietly and slowly, using a bright light which will immobilize them for a while. There are many methods of capture including using nets, spears, bows and arrows and angling. Use weapons only for adult bullfrogs so that there is no confusion between the juvenile bullfrogs and red-legged frogs. The animal care community has approved any method which rapidly severs brain function, such as decapitation. According to an article I recently read “the most humane way to kill the cold-blooded bullfrogs is to place them in a sealed container in the refrigerator for about 6-12 hours to kick in their hibernation instincts, and then place them in a freezer for one-two days.”. I’m not sure how the rest of the family will react to a fridge full of frogs however! Cajun frog legs?
Broom, gorse, tansy ragwort, rabbits, starlings and now bullfrogs; all these invasive species are having a huge impact on our natural ecosystems. However bullfrogs have just arrived in Metchosin and perhaps with a little knowledge and persistence we can contain or eradicate them before they cause irreparable damage. For more information, contact the Bullfrog Project or Bullfrog Control, listed below.
References:
Amphibians of Oregon, Washington and British Columbia by Corkran and Thoms
The Bullfrog Project: http://web.uvic.ca/bullfrogs
Bullfrog Control: http://64.246.185.201
Cajun Frog Legs Recipe from the Internet:
Ingredients: 16 good sized frog legs, 1 cup shortening, 1/2 cup flour, 3 cups milk, 1 tsp paprika. 1/2 tsp onion powder, 1/2 tsp garlic juice, 1/2 tsp ground cayenne pepper, 1/4 tsp black pepper, 1 dash white pepper, 1 dash oregano, 1 dash rosemary, salt to taste
Directions: Skin, clean and rinse frog legs well. Cover with whole milk and garlic juice in a plastic mixing bowl, refrigerate overnight. Pat dry, season with paprika, onion powder, cayenne, black pepper and desired amount of salt. Add white pepper, oregano and rosemary to the flour. Heat shortening in a skillet. Lightly flour the frog legs and fry until golden brown.
Himalayan Blackberry
Garden of Eden-Revisited
May 2, 2003
In a modern day interpretation of the story of Eve succumbing to temptation and taking that first mouth watering bite of the forbidden fruit; we would have a Metchosin family sitting down to their first of the season, wildly perfumed and fantastically flavoured blackberry crisp. It is hard to believe that something so exquisitely delicious can be so devastating for our environment, but given a moments inattention, it will destroy our little bit of Eden in it’s aggressive quest for global domination.
Himalayan (Rubus discolor) and evergreen (R. laciniatus) blackberry are introduced Eurasian weeds which tempt us with their ambrosia like qualities while transforming our native landscapes into thorny and impenetrable monocultures. Their long arching branches cascade 20 to 40 ft (6-12m) and where they touch the ground, new plants will form. Their rootstocks are large reservoirs which store the fuel needed to sustain their massive growth each season. Sharp, vicious thorns grow along the stems as well as on the leaves and leaf stems. Himalayan blackberry has leaves that branch like fingers from a grasping hand, with five large, oval, toothed leaflets; evergreen blackberry also has five leaflets which have very indented edges.
The Himalayan blackberry is the one most familiar to us as a favoured berry and noxious pest. It is the one you notice infesting hedgerows, meadows and parkland and it is partial to moist areas in either full sun or part shade. It’s habit of rampant growth quickly consumes most plants other than mature trees in it’s path. To be fair, it does offer food and shelter to birds and small mammals, although the original diversity of species has been greatly reduced. The birds are excellent dispersers of blackberry seed and the time spent inside the birds is thought to enhance the germination success of the seeds.
For those who wish to reclaim a portion of their original Eden, control of blackberries is a daunting prospect. There are several methods used to remove blackberries and they are the same for all species.
The first is physical control.
Small seedlings can be hand pulled.
For mature plants:
Remove the top growth in whatever manner is possible to you, with lopers, brush mowers or weedeaters. Mow repeatedly all year to prevent regrowth and deplete the energy reserves of the massive rootstocks. This can take three years so persistence is needed. Some suggest pouring boiling water over the cut stems at this point to try to kill off the roots. Mature plants can be hand dug, removing all roots to prevent resprouting. This should be undertaken in the wet season as the roots are easier to dislodge at this time. Disturb the soil as little as possible to discourage seedbank recruitment. The roots can be large and tenacious and the use of a pry bar, a three-clawed rake or a Pulaski (a tool that is half axe, half adz hoe that is used in making firelines) has been recommended. Pieces of cut root can resprout so be diligent.
In rocky, shallow soils goats are recommended, although they are the mammal equivalent of a non-selective herbicide and will also browse the native and other desirable plants.
The second is chemical control. These methods are endorsed by the Government of British Columbia in their Integrated Pest Management Manual for Landscape Pests in British Columbia (2000).
“The entire thicket must be mowed or cut down in May or early June to remove all woody top growth. The roots will sprout new shoots, which should be left to grow for the summer. In early September, treat the plants with the non-selective (can kill any type of plant) herbicide, glyphosate (Round-up or Vision). At that time of the year, the herbicide is readily translocated to the roots. The plants may not appear to be affected for some time, however, they do not grow back in the spring.” Never apply spray pesticides during windy conditions. Also from the BC Government, the Handbook for Pesticide Applicators and Dispensers (1995); “Glyphosate is quickly deactivated in soil, so no residue remains in soil to contaminate subsequent crops. It has a low acute toxicity to mammals, fish and wildlife, but may cause eye irritation. Rain within six hours of application reduces effectiveness.”
The use of herbicides should always be considered carefully and directions followed faithfully, using protective wear. Some people recommend using herbicides in a “cut and paint” manner. Within 5 to 20 minutes of cutting a weed stem, paint the cut area with the appropriate non-selective herbicide. This reduces the danger to humans and to other plants from spray drifting onto them.
Our native trailing blackberry (Rubus ursinus) or dewberry has leaves comprised of three leaflets and low growing, blue-green stems densely covered in small thorns. It has separate male and female plants and you can come across large patches that are all male plants devoid of fruit. First Nations used it for medicinal purposes as well as a foodstuff. The small berries are said to be even more delicious than the introduced varieties, although not so numerous and it is a parent of boysenberry, loganberry and youngberry. It is tolerant of many site conditions and was one of the plants that quickly re-established on Mt. St. Helens. It responds well to fire and logging and is an important winter browse for black-tailed deer. More than once it has jolted unwary hikers out of their reveries as the trailing stems seem to consciously reach out and trip the unsuspecting, bringing them down for a close view of one of nature’s valuable assistants.
References to Rubus ursinus from Plants of Coastal BC by A. McKinnon and J Pojar
May 2, 2003
In a modern day interpretation of the story of Eve succumbing to temptation and taking that first mouth watering bite of the forbidden fruit; we would have a Metchosin family sitting down to their first of the season, wildly perfumed and fantastically flavoured blackberry crisp. It is hard to believe that something so exquisitely delicious can be so devastating for our environment, but given a moments inattention, it will destroy our little bit of Eden in it’s aggressive quest for global domination.
Himalayan (Rubus discolor) and evergreen (R. laciniatus) blackberry are introduced Eurasian weeds which tempt us with their ambrosia like qualities while transforming our native landscapes into thorny and impenetrable monocultures. Their long arching branches cascade 20 to 40 ft (6-12m) and where they touch the ground, new plants will form. Their rootstocks are large reservoirs which store the fuel needed to sustain their massive growth each season. Sharp, vicious thorns grow along the stems as well as on the leaves and leaf stems. Himalayan blackberry has leaves that branch like fingers from a grasping hand, with five large, oval, toothed leaflets; evergreen blackberry also has five leaflets which have very indented edges.
The Himalayan blackberry is the one most familiar to us as a favoured berry and noxious pest. It is the one you notice infesting hedgerows, meadows and parkland and it is partial to moist areas in either full sun or part shade. It’s habit of rampant growth quickly consumes most plants other than mature trees in it’s path. To be fair, it does offer food and shelter to birds and small mammals, although the original diversity of species has been greatly reduced. The birds are excellent dispersers of blackberry seed and the time spent inside the birds is thought to enhance the germination success of the seeds.
For those who wish to reclaim a portion of their original Eden, control of blackberries is a daunting prospect. There are several methods used to remove blackberries and they are the same for all species.
The first is physical control.
Small seedlings can be hand pulled.
For mature plants:
Remove the top growth in whatever manner is possible to you, with lopers, brush mowers or weedeaters. Mow repeatedly all year to prevent regrowth and deplete the energy reserves of the massive rootstocks. This can take three years so persistence is needed. Some suggest pouring boiling water over the cut stems at this point to try to kill off the roots. Mature plants can be hand dug, removing all roots to prevent resprouting. This should be undertaken in the wet season as the roots are easier to dislodge at this time. Disturb the soil as little as possible to discourage seedbank recruitment. The roots can be large and tenacious and the use of a pry bar, a three-clawed rake or a Pulaski (a tool that is half axe, half adz hoe that is used in making firelines) has been recommended. Pieces of cut root can resprout so be diligent.
In rocky, shallow soils goats are recommended, although they are the mammal equivalent of a non-selective herbicide and will also browse the native and other desirable plants.
The second is chemical control. These methods are endorsed by the Government of British Columbia in their Integrated Pest Management Manual for Landscape Pests in British Columbia (2000).
“The entire thicket must be mowed or cut down in May or early June to remove all woody top growth. The roots will sprout new shoots, which should be left to grow for the summer. In early September, treat the plants with the non-selective (can kill any type of plant) herbicide, glyphosate (Round-up or Vision). At that time of the year, the herbicide is readily translocated to the roots. The plants may not appear to be affected for some time, however, they do not grow back in the spring.” Never apply spray pesticides during windy conditions. Also from the BC Government, the Handbook for Pesticide Applicators and Dispensers (1995); “Glyphosate is quickly deactivated in soil, so no residue remains in soil to contaminate subsequent crops. It has a low acute toxicity to mammals, fish and wildlife, but may cause eye irritation. Rain within six hours of application reduces effectiveness.”
The use of herbicides should always be considered carefully and directions followed faithfully, using protective wear. Some people recommend using herbicides in a “cut and paint” manner. Within 5 to 20 minutes of cutting a weed stem, paint the cut area with the appropriate non-selective herbicide. This reduces the danger to humans and to other plants from spray drifting onto them.
Our native trailing blackberry (Rubus ursinus) or dewberry has leaves comprised of three leaflets and low growing, blue-green stems densely covered in small thorns. It has separate male and female plants and you can come across large patches that are all male plants devoid of fruit. First Nations used it for medicinal purposes as well as a foodstuff. The small berries are said to be even more delicious than the introduced varieties, although not so numerous and it is a parent of boysenberry, loganberry and youngberry. It is tolerant of many site conditions and was one of the plants that quickly re-established on Mt. St. Helens. It responds well to fire and logging and is an important winter browse for black-tailed deer. More than once it has jolted unwary hikers out of their reveries as the trailing stems seem to consciously reach out and trip the unsuspecting, bringing them down for a close view of one of nature’s valuable assistants.
References to Rubus ursinus from Plants of Coastal BC by A. McKinnon and J Pojar
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