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Tuesday, May 26, 2009

TICKS!


Pacific Black-legged Tick (Ixodes pacificus)


DON’T BRING A TICK HOME FOR DINNER!
May 20, 2009

Which creature do you consider to have the highest revulsion factor rating?
When I wrote the recent article on Rats!, I’m sure some of you were squirming in your seats, shivering with memories of battles lost and won to rid your homes of rats. But rats do have their place in this world, as food for other predators, as recyclers of garbage, as scientific tools in the search for cures to human ailments.
I have been trying to think of a reason that ticks exist, how they might fit into our limited understanding of ecological interconnections. I suppose if you remove our human perspective of good and bad (for us), they have a place as a reservoir for bacteria, and maybe this plays a role in keeping populations in balance. There is a small parasitic wasp which lays its eggs in ticks and apparently guinea fowl consume them. Personally I find them really tough to appreciate, particularly when I find them latched onto some part of my anatomy.
Vancouver Island is home to about eight tick species but in Metchosin, the most common tick that you will find is the Western Black-legged tick (Ixodes pacificus). It is also the only one that will attach to humans. A walk through almost any natural landscape on a pleasant day from November through June will end with a few ticks trying to find a meal on my small dog, Maggie. Sometimes I’ll see them crawling over her white fur, looking for the safest location to settle and start feeding. Other times I will find them by accident as I give her a rub and feel a grey lump protruding, sometimes behind her ears or often on her forehead.
For two years I collected all the ticks I pulled off her, dropped them into a container of alcohol and eventually brought them to the Royal BC Museum, entomology (insect) section. They displayed a variety of colours, ranging from black to brown, grey, red and white and I thought I had at least several types of ticks in my little jar. Expert analysis pronounced all the ticks as Western Black-legged ticks in various stages of development.
These ticks have a four stage life cycle. Adults lay eggs that are deposited on leaves or in the leaf litter. The eggs hatch and the immature, minuscule ticks (larvae) immediately look for an appropriate host, usually small mammals. They attach to their host, feed on blood and detach. In their next stage, as nymphs, they again attach to a host - they prefer alligator lizards with deer mice a close second - feed, detach and molt. The top photo shows a northern alligator lizard on Camas Hill, Metchosin, with a tick attached, midway between the eye and front leg. As an adult tick, they prefer large mammals such as deer, cattle or humans, probably because they offer a large blood source to ensure their eggs a good start. They find their new hosts by climbing onto some low growing plants or grass. From here they exhibit behaviour known as questing, where they wave their legs in the air, sensing a prospective “mobile home” through organs which detect carbon dioxide and heat. In one survey adult ticks were found more often on south-facing hillsides, questing from salal, Scouler’s willow and wild rose; the same habitat where you’ll find alligator lizards. Adult ticks consume 200 to 600 times their unfed weight in blood.
The female tick can produce 1000 to 8000 eggs, after which she dies; the male dies after reproduction. Ticks in the larval stage are minute, the size of a poppy seed, while an engorged adult can expand to the size of a bean or grape. Studies have shown them to be more prevalent just after rain, with female adults reaching their peak populations in May.
Western Black-legged ticks can be carriers of Lyme disease, a potentially serious disease that can affect joints, the heart and the nervous system. There is some controversy as to the incidence of Lyme disease in ticks in this area with some studies showing a low (less than 1%) incidence while others claim up to 30% rate of infection.
In some US states, including California, they have (rarely) been known to pass on granulocytic ehrlichiosis rickettsia to horses, which can cause fever, loss of appetite, loss of coordination and various other symptoms.
Ticks inject an anesthetic that can prevent you from feeling them while they are feeding. If you are unlucky (like me!) and find a ramble in the hills has resulted in an unwanted hitchhiker, carefully remove the tick with tweezers placed firmly at the head, pulling gently and slowly but not twisting, allowing the tick to disengage its mouthparts. Try not to squish the ticks abdomen as this can expel contents from the tick’s stomach into the wound and thereby transfer disease bacteria. You can save a live tick in a jar with a dampened cotton ball, if you intend to send it for testing, but I just flush any I find down the toilet. Wash the bite area with soap and water and then swab with hydrogen peroxide or alcohol. I seem to break out in a swollen ulcer-like, tender wound which can be slow to heal but this doesn’t occur with everyone and does not mean that you have contracted Lyme disease, it is probably a reaction to the saliva. If you develop a fever or flu-like symptoms within two weeks to a month of the bite or a red bulls-eye rash, you might have contracted Lyme disease and you should see your doctor. There is a vaccine for dogs but we humans don’t have that safeguard yet. Two weeks on antibiotics is the recommended course of action. The Centre for Disease Control has an excellent brochure on Lyme Disease and ticks that can be downloaded, see the reference at the end of the article for the website.
There are other less common diseases that ticks can carry, so it is best to protect yourself from a bite in the first place. Don’t let the fear of ticks prevent you from exploring the countryside, hiking up hillsides and into the woods. Wear long pants tucked into socks, a long-sleeved shirt and a spray of an insect repellant such as Deet to reduce your chance of harbouring these creatures. And enjoy your hike!

References:
BC Centre for disease Control: http://www.bccdc.org/topic.php?item=83
http://www.phac-aspc.gc.ca/id-mi/tickinfo-eng.php
http://www.afraidtoask.com/lyme/lymelifecycle.html
Arnason, Carl, S. 1988. Biology of the Western Black-legged Tick, Ixodes Pacificus

Wednesday, May 6, 2009

Swamp Lantern Sex


SWAMP LANTERN SEX
April 7, 2009
Moralea Milne


Through the damp mist, glowing like a brilliant yellow beacon, the swamp lanterns rise from the wetlands and swamps to announce the rebirth of the landscape; what a wonderful sight for eyes tired by unrelenting grey skies. More prosaically know as skunk cabbage, this tropical looking member of the Arum family is one of the first plants to appear in March, or April if you have a cold winter such as this year. The eastern species can generate heat more than 30ºf warmer than its surroundings, melting ice and snow to emerge. Our western species (Lysichiton americanum) does not have (nor need) this ability but it has a few tricks of its own up its spadix.
The first scent, often overlooked, that is emitted from these harbingers of spring is a sweet, coumarin-like fragrance (coumarin produces a scent similar to new mown hay). Enticed by its flag of brilliant yellow and the “come hither” alluring scent, the winged rove beetle (Pelecomalius testaceum) arrives to feed on the pollen and in doing so, transfers the pollen so that the plant is fertilized. After gorging themselves at the pollen banquet, the beetles satisfy further primal urges and mate, retreating to the protective and hidden base of the spathe (yellow encircling leaf) and spadix (clublike stalk with hundreds of miniscule flowers). The skunky smell for which it is renowned comes later, when the flowers have wilted and the leaves are more fully developed.
The thick, fleshy roots are eaten by bears, and elk and deer browse the young leaves. This is an example of when you should not consider something safe to eat because animals eat it, seemingly with impunity. The plant contains crystals of calcium oxalate (also found in rhubarb leaves), which will cause intense burning, irritation and swelling if ingested. It was eaten in times of famine but only after thorough cooking.
The immense, almost tropical looking, verdant green leaves can grow to 1.5 metres and were used by many First Nation people to wrap food for steaming, apparently no odours were imparted to the foods. They were also handy for lining baskets for the berry harvests and in the cooking pits. Some First Nation communities used the leaves as a poultice for burns and injuries.
As their name suggests, swamp lanterns grow in swamps, where the soil is rich in nitrogen and usually has slow moving groundwater near the surface. They are usually found in association with red alder, western redcedar and lady fern.
Europeans have been renowned for centuries for their plant expeditions and for bringing new plants into their horticultural trade. Swamp lantern is one such plant that has been celebrated for its beauty and peculiarity and planted into European gardens and into natural areas “to enhance native flora”. To be fair, most of this was before the concept of invasive plants disrupting ecosystems was even a gleam in a scientist’s eye. Swamps are rare in Central Europe and now they are under attack from the invasive onslaught of our swamp lanterns which have successfully bullied their way into these habitats, shouldering aside the native flora. An ironic reversal of the usual direction of invasive species; many of our most common alien invaders have come from Europe and Asia.
Whether you call them skunk cabbage or swamp lantern they signal the rebirth of spring and the promise of sunny days ahead.


Reference:
R.T. Ogilvie, Pollination of skunk-cabbage March 1997 NPSG newsletter
Pellmyr and Patt, Madrono, 1986, 33 (1):47-54
Alien invasive species profile www.nobanis.org/files/factsheets/Lysichiton%20americanus.pdf
Pojar, J. and A. MacKinnon, Plants of Coastal BC
Hebda, Richard. http://www.npsbc.org/Newsletter/article01.htm

Friday, February 27, 2009

Rats!

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

Monday, February 9, 2009

Knees by Gala

This is a poem my daughter recently wrote:

Blank sheet – the urge to write – completely overtaken – no paper – want the scripture of my penmanship – to know it was me – to feel where I stopped – where I stalled – to remember what I was thinking – in that - moment – when I wrote what I wrote – when I wrote it – raining. Rain raining rain. Mother so strong very quiet has integrity never falters. Mother mother mom. Her knees are weak. But not the weak feeling that your knees get some times when your mind tells them to be. The weak that comes with years, decades, of hard work. Bending creaking cracking. Your knees. Your important knees. Running you through slippery streets and Manila rain. Deflecting the weight of your back and your head as you twist and twist dancing to that reggae beat and the bongo drum and flute. Covered in dirt from the garden soil, trembling below your catcher's mitt waiting for the pitch to come fast, spinning in circles with the rotation of bicycle pedals, exposed by the hole in the knee of your jean from where you tumbled when your feet digressed from your body's regular pattern. And now your knees are old. And now your knees are old. They rest, tucked into a nightie while you watch situation comedy. Earl grey tea.

Saturday, January 31, 2009

Bird Brain 101 Continued

Bird Brain 101 Continued
Moralea Milne
January 5, 2009

At the beginning of December’s snowfall, while the arbutus still held its crop of bright orange and red berries, a hermit thrush stationed itself in the tree by my kitchen window and rarely left until every last berry was consumed.
Over the past several weeks, as the snow continued to fall and our normal, mild winter temperatures never quite materialized, I hung out suet feeders on this same arbutus and enjoyed the never ending activity as juncos, Stellar’s jays, chickadees and other small songbirds flocked to this energy source. Next time I am going to make Isobel Tipton’s excellent recipe for suet cakes (see previous Muse).
On this early January morning, as the rain falls continuously on the wet snow and fog blankets the landscape, it seems a good time to contemplate changes that can be made to make a yard more bird friendly.
One of the biggest limiting factors to attracting birds is the scarcity of available nesting sites. Loss of habitat can occur for a variety of reasons. Some birds use abandoned woodpecker nests, but woodpeckers can’t drill a nest hole unless there is a suitable tree in the vicinity. Trees that are young often don’t have sufficient diameter or they are too healthy. Yes, a tree can be too healthy! Wood drilling birds prefer trees with some rot or broken branches, where the wood has been somewhat softened and is easier to drill. They might look unsightly to you but they look like prime real estate to a woodpecker. Some birds, like great-horned owls will nest in the top cavity of a broken-topped tree.
Invasive species, like starlings, English sparrows and gray squirrels have also reduced available lodgings by commandeering them for their own use.
Building a nest box will sometimes attract the species that are looking for a tree cavity. Chickadees, nuthatches, tree and violet-green swallows, house wrens, flickers, downy and hairy woodpeckers might come to carefully constructed and placed nest boxes. I’ve had good success attracting violet green swallows, using an odd shaped entrance hole, sort of a horizontal or vertical oval (22 cm x 8.9 cm), that is just a little too small for English sparrows to invade. It can be quite comical to see those fat little intruders trying to squeeze into the swallow nest. They’ll finally give up and the swallows can take up residence.
At a previous property we had built many nest boxes but they were all taken over by starlings and grey squirrels. The squirrels would enlarge the holes, chewing around the entrance until no self respecting flicker would consider it again. To solve this problem, you can fashion a metal plate and secure it around the hole. Placement is important too; a minimum of five feet above ground, out of the range of predators, away from direct sun (and overheated conditions) and protected from heavy rains. Most birds are secretive when nesting and don’t want their nests in full view.
Nesting materials can be hard to find. Hang short lengths of string and yarn (to 6 cm maximum), fleece, dried grass, bulrushes and cattails and small feathers and down in baskets or mesh bags in easy to find areas. Do NOT use dryer lint, which can swell and force young birds from their nests.
Constructing nest boxes can a fun family project. You don’t need a professional workshop or expensive materials for this project.
Use old bits of untreated wood or rough cedar, if you can leave the bark on, it will give a more natural look. Use screws and overlap sides to prevent water from infiltrating. Make one of the sections removable, it’ll facilitate fall cleaning. Drill a few holes just below the ceiling area, for ventilation and a few in the floor, to remove moisture. Do NOT add a perch, it gives easier access to those myriad creatures that consider eggs and young birds as tasty snacks. You can add a predator block easily during construction. This is a scrap piece of wood, fashioned to the inside of the nest box, over the entrance hole (with the hole cut out). It makes the entrance hole thicker and deters some predators from being able to reach the eggs or young.
Locate the box in a quiet area that is not too busy and consider if using baffles will deter marauders. Face the entrance hole away from the wind and tilt the box slightly forward to keep the rain from entering. Most birds prefer to nest in secluded locations but swallows like a clear sightline and a perching spot not too far from their nest. If building a robin or barn swallow nesting shelf, add a lip at the front so that the nest will not fall out during storms.
In the fall, clean out the box and pour boiling water into the interior, to destroy parasites. Leave the box up over the winter, some birds might use them for nighttime shelter.
Watching the antics of our native birds can brighten an otherwise dull and dreary winter day and being part of the process that enables them to breed and raise their young near you can offer a fun, activity filled afternoon to yourself and your family. For other bird enhancing stewardship ideas, you can read the Lawnchair Birding article from the June 2008 Muse issue (look under October 2008 archives).
References:
The Bird Garden by S.W. Kress
Naturescape BC, Caring for Wildlife Habitat at Home, Provincial Guide by S. Campbell and S. Pincott