Facts About Snowy Owls

Snowy Owl (Bubo scandiaca)

Field Notes:

Last Saturday a fairly large circle of migrating cackling geese were sitting in a circle around a lone white bird in the center on a frozen local lake. To our delight, the zoom on the camera revealed that it was a snowy owl! The bird had dark spots and appeared to be a young female. She sat on the lake huddled in her feathers surrounded by the geese that sat formally encircling her. 

Within just a couple minutes most of the geese on the lake had flown away, leaving the snowy owl alone. She silently floated over the ice and turning her head to peer at us from afar. Despite being in the middle of a frozen lake she seemed shy so we used the zoom on the camera to look from a distance. Snowy owls are not a common sight here in Ontario, but just a couple days before my father had seen in the neighborhood, flying silently, almost as if it was floating in the air. It was a very rare and exciting sighting in this area, and hopefully she has a good journey!

About Snowy Owls

The majestic snowy owl is a rare winter visitor in Ontario, living mainly in the the Arctic Tundra, father North than any other North American owl. They are large, white owls with some dark flecks (which is good for camouflaging) and yellow cat-like eyes that take up more space in the skull than its brain. Their feathers (also covering their powerful talons) keeps them warm in their cold habitat, as well chick's grey down feathers. Males are smaller and paler with small dark spots, whereas females are significantly larger with darker horizontal grey-brown lines. In both cases, younger adults adults ones have darker markings that pale with age, some older males being pure white.

Size: 51-69cm L

Unlike many other owls, snowy owls are largely diurnal, hunting during the day. These large, silent fliers will often sit perched somewhere high up out in the open, where (s)he can get a bird's-eye view and listen for prey. Snowy Owls prey mainly on lemmings, as well as ptarmigans, voles, and other small animals, coughing up undigested parts such as fur and bones in pellets. An adult will take prey back to the nest if it is breeding season. Parents tear up pieces of meat for the chicks while they are young, and when the owlets are older they swallow prey whole. When lemming and vole populations severely decrease, snowy owls may move south in search of food.

Snowy owls are sexually mature at 3-5 years old, and are generally monogamous. Clutches are laid in nests on the ground in the middle of the open Tundra with up to 12 eggs at one time when food is abundant, although when food is scare they may not breed for a year. The incubation period is 30-33 days, where the older eggs may be laid and hatched two or three days before the youngest.

Snowy owls are also territorial and tend to be aggressive when defending their territory or their young. Despite being typically silent, they may be vocally aggressive with a raspy call or a shriek if it is a female. They may be physically aggressive if a potential predator (such as a fox, human, or even a wolf) gets too close to the nest and threatens their young. Unfortunately their population is one a decreasing trend, one cause being hunting, but their their conservation status on the IUCN redlist as of December 21, 2013 is least concern.

References

T, Travis. 2001. Snowy Owl. Blue Planet Biomes. Retrieved from http://www.blueplanetbiomes.org/snowy_owl.htm.

Bishop, Gerry.  http://www.nwf.org/Kids/Ranger-Rick/Animals/Birds/Snowy-Owls.aspx

IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. <www.iucnredlist.org>. Downloaded on 21 December 2013.

Parmelee, David F. 1992. Snowy Owl (Bubo scandiacus), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online:http://bna.birds.cornell.edu/bna/species/010

The Real Costs of Parathion

     The conflict of human convenience and the wellbeing of ecosystems is a repeating issue. Parathion (usually  referring to ethyl parathion, sometimes methyl parathion), is an effective insecticide and one of the most toxic organphosphates, proved to be sometimes fatal to humans and other animals. The original intent for producing and using parathion as an insecticide are not malicious, however with more recent information the risks have become more apparent. The convenience of using parathion is not worth the consequences to natural ecosystems and human health.

An Effective Method

     Parathion is an effective and relatively cheap insecticide. It kills unwanted insect 'pests' by disrupting their nerve impulses. Pest control has played a large role in farming and the mass production of food to feed millions of people, and is also part of the monetary success for individual farmers and overall economies. Pesticides are especially needed for monocultures of food that resulted from the Green Revolution of mass factory farming, as an entire culture would be susceptible to unwanted insects. The method of factory farming has helped humans avoid Thomas Malthus' prediction that starvation would overtake the world by the year 2000, however, the use of pesticides is among the many rising issues associated with factory farming, and there are safer options than parathion such as introducing a natural predator or genetically modifying crops so that they are less susceptible to the pest. Many organic farmers have successfully raised crops without the use of any pesticides, as all pesticides do have the potential for adverse side effects. One of the reasons parathion is used is because its high toxicity makes it highly effective, but it also highly effective on other non-targeted species.

A Toxic Threat

     Other living things are not immune to the devastating effects parathion has on an organism, Parathion has proven to be especially toxic to birds such as grouse, pigeons, red-winged blackbirds, and sparrows. Amounts of dermal exposure may be fatal for birds such as house sparrows, which have 50% mortality rate after 24 hours of dermal exposure of 1.8 mg / kg on their feet. Not only do they receive exposure through the air when it is sprayed, but also because of what they prey on. Ethyl parathion has been pinned as the direct cause of death for birds in numerous instances, for example the death of fourteen Mississippi kites from insects that were contaminated by parathion in a nearby cotton field in 1994. Another occurrence was in 1982, New York, when almost 3200 birds of various species were found dead in a field containing scattered rye seeds contaminated with ethyl parathion. As birds consume contaminated seeds and insects, bioaccumulation and biomagnification occur and the buildup of parathion in their systems often kills them, and can also impair some birds exposed to nonlethal doses in terms of ability to avert predators, and reproductive behavior (such as with the mallard and bobwhite) though it is unknown whether or not parathion affects reproductive ability.

     Parathion also has the potential to damage ecosystems by damaging other wildlife. Damage to aquatic invertebrates with ethyl parathion occurs with an EC50 at less than 1.0mg/L. On an acute basis it is also toxic to fish, with the potential to throw off the delicate balance of many aquatic ecosystems with water contamination. This would have a negative impact on entire ecosystems and communities whose economies and jobs depend on the fishing industry. Honeybees also play important roles in their ecosystems as pollinators, and they too are highly susceptible to the toxicity of parathion. Pollinators are necessary for growing plants in both natural ecosystems and in growing crops for humans in farms.

     Humans are also vulnerable to the health hazards of parathion, especially those who work with the chemical or live near landfills where it is disposed of. Parathion is a carcinogen and endocrine disruptor, and has been reported to have cause an influenza-like state and has also been associated with indirect brain impairments, such as disorientation, memory loss, decreased ability to concentrate, confusion, and delayed reflexes. It has also been linked with emotional disorders such as severe depression and insomnia. Nerve damage occurs because parathion is a cholinesterase-inhibiting chemical, which prevents the breakdown of acetylcholine when it is no longer needed to trigger physical reponses to nerve impulses. The buildup of acetylcholine causes the impulses to be repeated uncontrollably, with potential direct symptoms such as muscle spasms, trembling, paralyzed breathing, irregular heartbeat, convulsions, involuntary bowel movement, and in the most extreme cases, coma or even death.

     Considering evidence proving a direct link between various adverse effects parathion has on the health of other animals such as birds, aquatic invertebrates, fish, pollinating insects, and humans, the risks are obvious and severe. The potentially risks outweigh the benefits of convenience as the real cost goes beyond monetary values, but takes a toll on health of natural ecosystems, humans and other animals.

Sources

Bird Conservancy. (n.d.). Pesticide Profile - Ethyl parathion. abc birds. Retrieved December 12, 2013, from http://www.abcbirds.org/abcprograms/policy/toxins/profiles/ethyl_parathion.html

EXTOXNET. (n.d.). Cholinesterase Inhibition. EXTOXNET. Retrieved December 12, 2013, from http://extoxnet.orst.edu/tibs/cholines.htm

The Encyclopedia of Earth. (2008, August 1). Health effects of methyl parathion Edit Classification Publishing Workflow . The Encyclopedia of Earth. Retrieved December 12, 2013, from http://www.eoearth.org/view/article/153408/

Pesticide Information Center. (n.d.). Parathion. EXTOXNET. Retrieved December 12, 2013, from http://extoxnet.orst.edu/pips/parathio.htm Reuber, M., & Cooper, S. (n.d.). PARATHION (Ethyl parathion). Beyond Pesticides. Retrieved December 12, 2013, from http://www.beyondpesticides.org/pesticides/factsheets/parathion.pdf

The House Centipede: A Most Unique Roommate

House Centipede (Scutigera coleoptrata)

     According to some sources they grow up to 3 cm long, but they definitely grow bigger at our place. The first time there was a house centipede in the kitchen the first thing that came into my mind was that it looked like something from a sci-fi movie (think Star Trek TNG "The Entity").

     They have up to 15 sets of legs as full-grown adults and may live for up to seven years. The two front "legs" are actually venomous spikes used to paralyze its prey, and its legs stick out the side of each segment. They seem to be very high on the food chain, as the spiders and silverfish in our house slowly started disappearing and we saw more and more house centipedes.

     So, do you have to worry about being stung or bitten by a house centipede? The Ontario Nature Guide by Krista Kagume says, "Although Ontario house centipedes don't generally harm people, they can inflict a painful bite when handled." Avoiding being stung is pretty simple: don't play with it.

     Something else I didn't know until an encounter is that they play dead... or at least that's how it appears. Once my dog attacked a house centipede. She picked it up between her teeth and whipped it around a bit before dropping it onto the ground. The centipede lay there and didn't move. I tried to make it get up with a pencil in hopes of bringing it outside, but it didn't even flinch. Just after we both left the room, I peeked back in and saw the insect get up and run underneath a bookshelf (clever little trickster).

     Like lots of other kids, I used to look for spiders and insects in the house to name and play with and blow kisses to, but for some reason I became a total scaredy-cat around that house centipede. I believe in the theory that fear of insects is a learned fear, as we learn to be afraid of things that we don't know about, of things that are different from our version of normal.

     Here is a tip to anyone who has an irrational fear of any creature: learn its role in the ecosystem. Sometimes all it takes it to unshroud something from mystery for it to be not so scary anymore.

References

Kagume, K., Kershaw, L. J., & Bezener, A. (2008). Ontario Nature Guide. Edmonton: Lone Pine Pub..

Local Bird: Cedar Waxwing

Cedar Waxwing (Bombycilla cedrorum)

Physical characteristics: 

     Cedar waxwings have very slick, smooth look with a gradient brown or orange to yellow body. A few red spots stand out on grey wings, and, and with yellow terminal tail band (the tips of the tail feathers is yellow)on a grey tail with a white undertail. The cedar waxwing has a crest and a black mask and beak, giving it a "heroic" look. The cedar waxwing is about has a 30cm wingspan and the ones I have seen are about the size of a robin.

Habitat/range: Wooded areas and fields throughout Ontario during the breeding season.

     Cedar waxwings are very social birds and are often seen in flocks, especially around areas with fermenting berries to feast on. During migration they may even be seen in flocks of hundreds or occasionally even thousands. They might be seen lined up, passing down berries to share until an individual decides to eat it, and then another berry is picked to be passed down the line again. This endearing behaviour is also seen in a cute courtship dance where the male will hop towards the female, offering her a berry. After accepting the berry, she hops a little way with it before stopping to hop towards him again to offer it back to him, and the dance repeats.

     They build nests out of twigs, lichen, and moss in both coniferous and deciduous trees and shrubs. A female lays 3-5 eggs at a time, with an incubation period of 12-16 days. The cedar waxwing's call is high, lisping, and trilling.

Distinguishing a Bohemian Waxwing (Bombycilla garrulus) from a Cedar Waxwing:

They have a  similar appearance, but are distinguishable by both physical traits and range during certain times of year.

• Bohemian Waxwings have a grey chest and belly, and red-orange undertail.
• Bohemian waxwings are slightly larger.
• During breeding season bohemian waxwings live in Northern Canada, Alaska, and high Northwestern American mountains. Unless you live in one of those regions, if it is Summer, spring or early fall then it is a Cedar Waxwing.

Field notes:

     This summer I got to see two cedar waxwings within two days of eachother. This might be due to the fact that they are often in flocks so although at the time they were both alone (once perched on a tall branch and once sitting in a mulberry berry tree), the rest of the flock might have just dispersed somewhere nearby.

    The two cedar waxwings also had different appearances. The first one was in a tree by a lake with a gregarious set of more intense colours and posture (the orange was very clear), whereas the other had slightly more neutral colours (a paler yellow and more mousy brown than orange head), with a more mysterious and intriguing beauty. Its appearance was especially similar to a bohemian waxwing's in the shade, however the undertail was white and it was summer in Ontario so it was indeed a cedar waxwing.

References

Bezener, A., Kagume, K., Kennedy, G., & Adams, C. (2005). Compact Guide to Ontario Birds. 

     Edmonton: Lone Pine Pub.

"Corey". (n.d.). Cedar Waxwing vs. Bohemian Waxwing. 10,000 Birds. Retrieved December 3, 

     2013, from http://10000birds.com/cedar-waxwing-vs-bohemian-waxwing.htm 

Kagume, K., Kershaw, L. J., & Bezener, A. (2008). Ontario nature guide. Edmonton: Lone Pine.

Cornell Lab of Ornithology. (n.d.). Cedar Waxwing. All About Birds. Retrieved December 1, 2013, 

     from http://www.allaboutbirds.org/guide/cedar_waxwing/id

National Geographic. 2006. Cedar Waxwing. http://animals.nationalgeographic.com/animals/birding/cedar-waxwing?source=A-to-Z

A Few Highlights From the Pinery

     This summer we went camping with another family to the Pinery in Grand Bend. The Pinery is in the middle of the Carolinian forest and is home to the tulip tree. Tulip trees produce intricate and vibrant flowers in the warmer months, and their leaves are actually shaped similar to the silhouette of a tulip. The tallest tulip tree at the Pinery is estimated to be about 80 feet tall, possibly being the tallest tulip tree in Ontario.

     We had the opportunity to speak to two naturalists at the park, (who we will call "A" and "S" in this entry), who answered all of our questions about the park and the variety of species in it. I tried my best to journal all the places we visited and species we saw, but there was such a wide variety that ended up resorting to listing to keep track of it all. 

Here are a just few highlights from the trip:

      We saw a tiger moth with an asymmetrical wing, and a mother grouse with about six or seven little ones walking by the side of the road. We also learned some interesting things about photosynthesis from A. First of all, not all plants photosynthesize. There are at least two species of non-photosynthesizing plants at the Pinery: Indian pipe and cancer root. Also, the reason why some of the middles of Victoria Creeper plants is red is actually to almost attract or funnel more light in shady areas. A also explained that different stalks of Victoria creeper, joined at the roots might even dedicate all energy to one single plant for that individual plants survival because it has the greatest potential.

     On the Carolinian trail guided by two naturalists at the Pinery, we came to a stop and S began telling us about cicadas. When we stopped, a little girl from our group immediately noticed something small and brown on a blade of grass a few meters away and whispered to me, asking what it was. I tried to see but it was half-covered by the grass and I couldn't tell what is was. "Maybe you can ask her once she's finished," I whispered back.

     "... and sometimes, you might even find a cicada's exoskeleton still clinging to a tree trunk," the S said.

     "Like that?" The little girl asked, running over to the little brown dot and picking it up. She did in fact find a cicada exoskeleton with perfect timing. 

     Back at our campsite I also got the opportunity to commune with a small bee-like insect nicknamed "Marshy," who buzzed around for about an hour, and found a mysterious, spikey red and yellow female spider with her smaller, black mate spinning a web in our car window, later identified as Arrowshaped Micrathena (edit: see post Arthropod Mysteries From Camping at http://naturenimbus.blogspot.ca/2014/01/arthropod-mysteries-from-pinery.html).

     These are only a few highlights from our camping trip at the Pinery. If you are looking for a campground with biodiversity but no bears (plus some pretty clean campground washrooms) then I definitely hope you get the chance to experience the Pinery.

Indian Pipe

Cancer Root

(above) Female Arrowshaped Micrathena

(below) Her presumed mate.

White Yarrow

The top of the Lookout Trail

Plume Moth

Emperor Sumac (a poison ivy look-alike)

Field pennycress?

Tiger moth with an asymmetrical wing

White-tailed deer (doe)

Tulip tree (right is a sapling)

Canada Columbine

'Marshy'

Variegated Fritillary

Black-eyed Susan and St. John's wort

Wild turkey

A bent tree

 

Black squirrel

'Sticky' the Green Inchworm

Little Wood-Satyr

Butterfly milkweed

For more spottings visit my Project Noah spotting page (http://www.projectnoah.org/users/MelodyJT).

The Shape of a Raindrop

     Despite weather channel depictions and after years of drawing raindrops with a pointed top and rounded bottom, I was surprised to learn that raindrops are not shaped like teardrops.

     Air resistance is not the cause of the typically-drawn shape that appears as raindrops streak across windows or on peoples' face when we dry; that is caused by surface tension of the liquid water on the surface.

     As they fall through the air, raindrops are actually spherical in shape. Smaller raindrops have less air resistance so they are more spherical than larger ones. The larger the raindrop, the more air resistance there is, and greater air resistance actually just flattens the bottom; a pointed tail/trail is actually not formed by air resistance. When a raindrop gets large enough (usually more than 4mm), it will actually split in half and drastically decrease in surface tension, possibly splitting so small that the water just rejoins as moisture the atmosphere.

Sources

Baird, Christopher S.. What Makes Raindrops Tear-Shaped? December 17, 2012 Science Questions with Surprising Answers. http://sciencequestionswithchris.wordpress.com/2012/12/17/what-makes-rain-drops-tear-shaped/

Oblack, Rachelle. The Shape of Raindrops. http://weather.about.com/od/cloudsandprecipitation/a/rainburgers.htm

How do geese keep their feet warm in the winter?

     While watching the migrating geese resting on a lake with a coat and hat and gloves on and still feeling chilly, it's amazing to see the birds swimming atop the icy waters. Sometimes I imagine being a goose, duck, or swan migrating during the winter. Unlike some birds that seek shelter from the elements, they remain on the water. Although they have waterproof feathers atop down feathers to keep their bodies warm, their feet are still exposed to the icy waters yet they are not frozen.

     The key lies in counter-current heat exchange. In the legs of ducks, geese, and other types of birds, the arteries (blood flowing away from the heart) have branches that are very close to branched veins (blood flowing towards the heart), allowing the warmer blood flowing towards the feet to cool, and warming up the blood coming up from the feet. This way, the foot is kept colder; without the branched blood vessels, the blood that reaches the foot is still warm.

     At first it might not seem to answer the question, as it seems to be that they keep their feet warm by making their feet cold? Well, the point is not to keep their feet warm, but it is to make them colder so that the heat needed in other parts of the body is not lost. This works because body heat is lost when the outside environment is colder than the exposed tissue, so the less the different in temperature in a goose's exposed feet with the water, the less body heat will be lost. To reduce the amount of heat lost, they also reduce their surface contact with ice which (according to askanaturalist.com) is the reason why you might see them balancing on one foot at a time. 

     Heat exchange also prevents cold blood from cooling down the parts of the body covered by feathers as the blood flows back towards the heart in the veins.

     This heat exchange is also applied when a bird is in a very hot environment, as it keeps it from overheating, as well as with other animals such as marine mammals, which have a net of branched veins and arteries around their bodies below their skin to protect them from the cold in addition to fat insulation.

Sources

AskANaturalist.com. Why Don't Ducks' Feet Freeze? Ask A Naturalist. Retrieved from http://askanaturalist.com/why-don%E2%80%99t-ducks%E2%80%99-feet-freeze/

Eccentricscheinstist.wordpress.com. Why Don't ducks get Frostbite? Wordpress. Retrieved from  http://eccentricscientist.wordpress.com/2007/01/13/why-dont-ducks-get-frostbite/

About a Bustard -Kori Bustard (Ardotis kori)

Kori Bustard (Ardotis kori)

(photo coming soon)

Conservation Status: Least Concern

Habitat: South and Eastern African grasslands and wooded areas

Physical characteristics: Long neck grey neck and head, long beak,  As a species, the kori bustard is the world's heaviest flying bird, the males weighing up to about 18 kg (39.6 lbs). They display sexual dimorphism, as males may weigh up to twice the weight of females, though they have similar plumage.

Lifespan: The longest recorded lifespan is 26 years in captivity, and there is approximately 86% mortality rate amoungst chicks in the wild.

Notes:

     One of 25 species of bustard, like other bustard species the kori kustard does not typically engage well with humans and will shy away from human contact. Generally they remain silent, however if alarmed they will make a loud barking sound, as well as displaying a "shock display" where the bird bends forward with its tail feathers lifted and spreading out its wings to appear larger than its actual size to predators.

     Their omnivorous diet consists largely of insects, however they also sometimes feed on smaller vertebrates such as lizards, snakes, birds, and small mammals. They also eat fruits including berries (and Tsamma Melons, see "What animals (besides humans) eat watermelons and pumpkins?" post), as well as nuts and Acacia tree gum (hence its alternate name Gompou' which means "gum eating"). They also have the rare habit of sucking up water when drinking. Its predators include eagles, lions, and jackals. Carine bee-eaters (Merops nubicus and Merops nubicodes) will sometimes perch on the back of an active kori bustard and eat the bugs disturbed by the bustard's activity, and may help the bustard detect predators.

     In courtship, the male will inflate his esophagus (up to a peak of four times its regular size), point his crest up and his wing and tail feathers down, and make a low booming noise to attract a female. Males will often perform this together in a group. The rearing of chicks is up to the mother, whose nest is a scrape in the ground with an in-captivity incubation period of 23 days.

Sources

Smithsonian National Zoological Park

     http://nationalzoo.si.edu/SCBI/TropicalEcosystems/KoriBustards/biology.cfm

     http://nationalzoo.si.edu/SCBI/tropicalecosystems/koribustards/default.cfm

Arkive.org.

     http://www.arkive.org/kori-bustard/ardeotis-kori/image-G62000.html

What animals (besides humans) eat watermelons and pumpkins?

     Considering their hard, thick exterior, it takes a level of skill to eat a pumpkin or melon.

(Ice Age, image source: animatedviews.com)

     Tsamma Melons, a relative to watermelons you would find the the grocery store, grow wild in the Kalahari desert is South Africa. Storing large amounts of water and resistant to drought, they are a good water source as well as food source for animals living in the region, including humans and kori bustards.

     If you grow watermelons in a garden in North America you might end up sharing them with some wild neighbours. Raccoons, deer, coyotes, and especially crows are all animals that might eat a watermelon if they found one.

     Despite being at the top of the food chain, coyotes also will eat watermelon. At night a coyote might sneak into a garden where it will break open a watermelon and eat the flesh right down to the rind. 

     The coyote's distinctive destruction to the fruit contrasts with the method which raccoons and deer eat watermelons. They will dig or puncture a hole through the skin to get to the inside.

     Pumpkins, too, are a reason for wildlife visitors in some gardens. Rabbits only eat the leaves (not the fruit itself), nibbling at the tips, similar to it's habitual sampling of leafy greens. 

     Using their digging abilities, mice and moles get to the seeds inside pumpkins by digging a tunnel through the bottom and into the middle. Squirrels, and chipmunks may also dig through a pumpkin in pursuit of the delicious seeds that await inside, sometimes even being found digging through pumpkins left of porches. Unlike the others, woodchucks eat the actual flesh of the fruit.

Sources

Bauer, Mary. What wild Animals eat Watermelons in a Garden? 

http://homeguides.sfgate.com/wild-animals-eat-watermelons-garden-40477.html

Kane, Dan. Tsamma Melons: Watermelon's Wild Cousins.

http://blogs.worldwatch.org/nourishingtheplanet/tsamma-melons-watermelon%E2%80%99s-wild-cousins/

http://www.arkive.org/kori-bustard/ardeotis-kori/image-G62000.html

http://pumpkinnook.com/howto/gardenpests.htm