Category Archives: Wildlife

Interpretive Blogs about Wildlife and Plants

Common Loon (Gavia immer)

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If the call of the loon “were of human origin,” author John McPhee once wrote, “it would be the laugh of the deeply insane.”

Loons in our Lakes by J. McPhee
Common Loon (Unsplash Royalty free by Kevin Crosby)

Common Loons have deeply insane diving and underwater skills and some wildly crazy vocalizations.

Loons capture fish by swimming through through water. This torpedo-like attack is fueled by short, strong legs and webbed feet that provide excellent underwater speed and maneuverability.

Olympic swimmers would envy the Loons ability to make abrupt 180-degree flip turns in seconds. They would also be amazed at how the birds are able to dive without a splash and reach depths of over 200 feet. Even newly hatched chicks are able to make shallow dives to escape predators.  

How do Loons swim like that?

To start with, Loons have web feet that are placed far back on their bodies. Four hundred different species of birds have webbed feet, as well as, otters, frogs, and salamanders. Web feet spread out to push the water backwards. The toes fold together minimizing water resistance on the forward stroke.

Webbed-feet are hard to walk with. In the case of the Loon feet are placed near the back of the body making it even more difficult, some say comical, for the bird to walk on land. To experience this problem, slide on a pair of large swim fins and try to walk across the lawn. Now you know why loons spend so much time in the water and only come near shore for nesting.

Loons are less buoyant than most flying birds. Loons have heavy, solid bones that serve as underwater ballast and help them dive deep. The bones of most other flying birds are hollow and filled with air.

These birds expel air out of their lungs and plumage when diving. This reduces water resistance and buoyancy and creates a very streamlined body shape. At the same time, their heart slows down to conserve oxygen and they are able to maintain the dive for several minutes.

What are they eating?

These extraordinary swimming skills are needed to capture fish, their diet mainstay. Some fish have erratic swim patterns and are easily caught by the Loon (this includes Bluegill and Yellow Perch). Fish that swim straight ahead (like salmon and trout) are more difficult.

Fish are caught underwater and often swallowed head first. Sometimes larger fish may be brought to the surface. Other prey may include crustaceans, crayfish, snails, leeches, lobsters, insect larvae, mollusks, frogs, worms, and occasionally aquatic plants.

Adult loons may eat up to two pounds of fish per day, and a loon family with two chicks may consume over 900 pounds of fish over the course of a breeding season.

How well do they fly?

Loons can fly ~70 mph and routinely migrate. They are like a jumbo-jet—they need a lot of space to take off and land. At times, a Loon can become stranded and unable to take-off if the pond is too small. They are not able to take-off and fly from land.

Loons are fast flyers and have a wide territory in the coastal U.S., and northern U.S. and southern Canada. Many migrate and over winter in coastal areas. Some migrate south into Baja California. In all cases, they will only stay in waters that are crystal clean and well populated with fish.  

Loon call

Loons are often identified by their eerie, and unusual calls. They use a tremolo call (that sounds like crazy laughing) when alarmed or to announce their presence and soft hoots to keep in contact with their young and each other. Each male loon also has a unique yodel used to identify territory.

To hear these calls see the Loon Preservation Committee website (https://loon.org/the-call-of-the-loon/). There is a good chance that you will have heard these calls in the movies (such as “On Golden Pond,” “Finding Dory,” and several others.

REFERENCES:
–Loon Preservation Committee (https://loon.org/about-the-common-loon/)
–Oregon Dept. of Fish and Wildlife, Loons and Grebes (ODFW  https://myodfw.com/wildlife-viewing/species/loons-and-grebes)
–The Cornell Lab, Cornell University, (https://www.allaboutbirds.org/guide/Common_Loon)
–Audubon Society (https://www.audubon.org/news/webbed-feet-are-evolutionary-hit)
–Wikipedia, Common Loons (https://en.wikipedia.org/wiki/Common_loon)
–”Loons in our Lake” (https://www.lifeinthefingerlakes.com/loons-in-our-lakes/)

Osprey (Pandion haliaetus)

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What lives in those exposed large, stick nests built on power poles, communication towers, and large trees? Most likely an Osprey.

Osprey image from Oregon Department of Fish & Wildlife

As you can imagine, a bird with a nearly 6-foot wingspan builds a big nest. Now imagine the bird adding a bit more to its nest each year. In the end, it is hard to imagine a nest becoming, over time, 10–13 feet deep and 3–6 feet in diameter!

Nest Challenges

Osprey build big nests and will build on any natural or man-made structure that meets its needs. Sometimes, what looked like a good choice doesn’t work out. Osprey nesting has caused power and service outages. There is always a risk of being electrocuted or collisions.

An Osprey’s nest contains more than just sticks we can see. Moss, bark, vines, grass, and lichen make the nest comfortable. But the birds will also add in other interesting things such as fishing line, baling wire, Styrofoam, and sometimes even plastic containers. Baling wire and fishing line can be fatal if the birds or young become entangled.

Nesting platforms and mitigation techniques reduce these conflicts and increase the number of birds and survival. The species is considered a conservation success story.

Where to see them

You can find Osprey nests near a lake, pond, swamp, reservoir, river, etc.  Live fish is key part of their diets unlike other raptors. They will also eat other smaller birds, snakes, voles, squirrels, muskrats, and salamanders.

Feet first!

Osprey are amazing fishers. Part of their fishing success, compared to other hawks, is undoubtedly due to an unusual toe/claw placement that helps them grip fish tightly. Their real success, however, is in technique.

The technique? Osprey dive feet first into shallow waters (up to about 3 feet) and grab a fish. They will also do this in deeper water where fish swim near the surface. Osprey have water-resistant feathers are the only raptors that dive.

Amazing Migration

In recent years, the number of Osprey residing year-around on the Pacific coast has increased. Normally, the birds would migrate as far south as Honduras. Researchers have found that some Osprey will migrate around 160,000 miles in their lifetimes. They are not sure what is causing this change.

Protection

Osprey are an amazing raptor and are protected by the Migratory Bird Treaty Act (MBTA) 16 U.S.C. Sections 703-712 of 1918 (as amended). All active nests (incubating adult, eggs, or young present) of migratory bird species are also protected by the MBTA. In Oregon, Osprey are protected by both state statute and Oregon Department of Fish and Wildlife administrative rules. Oregon Revised Statute (ORS 498) protects osprey from take, disturbance and harassment. Oregon Administrative Rule (OAR) 635-044 0130 categorizes osprey as Nongame Protected Wildlife. It is unlawful for a person to hunt, trap, pursue, kill, take, catch, or have in possession, either dead or alive, whole or in part, any Nongame Protected Wildlife.

References and where to find out more…Check the Oregon Department of Fish & Wildlife site at https://myodfw.com/wildlife-viewing/species/raptors and be sure to download their “Living with Wildlife” brochure at https://www.dfw.state.or.us/wildlife/living_with/docs/osprey.pdf. Another excellent resource is the All About Birds page by the Cornell Lab (see https://www.allaboutbirds.org/guide/Osprey/id).

Coyote (Canis latrans)

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Coyote (photo courtesy of ODFW)

Where did you first learn about coyotes? It may have been through children’s cartoons. The characters ‘Wile E. Coyote’ and the ‘Road Runner’ cartoons recreated the relationship between predators in a humorous way. Unfortunately, the representation is not very accurate.

Coyotes are North America’s oldest indigenous species. The oldest modern coyote fossils date to 0.74–0.85 Ma (million years) and can be found in Hamilton Cave, West Virginia. Coyotes are thought to have originated near Yellowstone three million years ago!

Habitat

Coyotes are found throughout Oregon. Their territory stretches south to Central America and north through much of Canada.

There are 19 different subspecies of coyotes inhabiting different areas. They look similar in that they are medium in size with multi-colored coat, and bushy tail.

Coyotes are part of the Canidae family which include wolves (typically larger) and foxes (typically smaller). These three species avoid using the same territory at the same time.  

Conflicts

As populations flourish, are they a nuisance? Conflicts between humans and coyotes usually occur as a result of human errors, often related to making food available.  And, because of the cartoon, we all know that the coyote is always hungry and looking for its next meal.

See Living with Coyotes fact sheet from the Oregon Dept. of Fish and Wildlife (link in References).

Diet

Coyotes will eat just about anything and will shift their diet seasonally and based on availability. If they have to eat grasshoppers to survive, they will. On better days they will be looking for mammals (such as rabbits, porcupines, rodents, squirrels, deer, goat, mice, etc.), fish, amphibians, , and reptiles, fruit and vegetables, and in times of food shortages invertebrates (like grasshoppers), farm animals (like chickens) and even pets. Coyotes also hunt in packs, usually for larger prey.

Communication

Unlike the cartoon, coyotes are intelligent and adaptable, and use a highly developed communication system to maintain long-term social and family relationships, and identify territory. Coyotes are considered to be the most vocal of all [wild] North American mammals.

Their howl, or group howls, are easily recognizable. They will also vocalize greetings, which can include a group yip howl.  Sounds can also include agonistic/alarm, and contact which may be made through woofs, growls, huffs, barks, yelps, and high frequency whines. Yelps are a sign of submission.

Vocalizations are also important, and often heard, during breeding season (generally between late January and March). Coyotes form strong pair bonds for several years and are generally monogamous.

These vocalizations always include some body language such as tail wagging, muzzle nibbling, and posture. An aggressive coyote will arch its back and lower its tail, head moving side to side, with spins and dives. Aggression is a normal behavior in a pack and fights are often silent.

Folklore

Native American folklore contains many references to coyotes. Coyotes may take the form of a trickster, skin walker, or in military/hero symbols, often as savvy and cunning. In Mesoamerica, the Coyote appears in several codices as the god of dance, music and carnality (sometimes as a womanizer). The Coyote also has parts in many creation stories from several native cultures.

Coyotes are an evolutionary success story. Their cunning, adaptability, communications, and ability to understand human behavior makes them stand out both in folklore and in modern times.

REFERENCES:
–Oregon Dept. of Fish and Wildlife (https://myodfw.com/wildlife-viewing/species/coyotes-wolves-and-foxes, https://www.dfw.state.or.us/wildlife/living_with/coyotes.asp)
–National Geographic (https://www.nationalgeographic.com/animals/mammals/c/coyote/)
–Wikipedia (https://en.wikipedia.org/wiki/Coyote, https://en.wikipedia.org/wiki/Fast_and_Furry-ous)
–The Howling: Why You’re Hearing Coyotes This Month (https://blog.nature.org/science/2019/02/13/the-howling-why-youre-hearing-coyotes-this-month/)
–Singing Coyote – the Ultimate Adapter (http://followingdeercreek.com/coyote/)