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American dipper (Cinclus mexicanus)

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The American dipper appears as a small nondescript bird found along the west coast from Panama to Alaska. Take another look. Sometimes big surprises come in little packages.

American dipper

What makes this species special? Why is this nondescript, dark brown to gray bird amazing? It doesn’t look amazing, but don’t judge too quickly… several things make them very special.

Indicator Species

Think of the old reference to a ‘Canary in a Gold Mine.’ Canaries were used as an indicator species for the mining industry. Canaries are very sensitive to methane and carbon monoxide. Early mines did not have ventilation systems and could be very dangerous. As long as the canaries were singing, it was safe.

American dippers are very sensitive to pollution and are only found on rushing, unpolluted streams.  They look for streams with rocky bottoms and overhanging banks, and areas with adequate nesting locations.  

If you were thirsty and lost, the sight of an American dipper near or in a stream is a sure indicator of good water quality.

Diver Extraordinaire

American dippers hang out near stream edges, bobbing up and down on long legs, and foraging aquatic insects and larvae, crayfish, and caddisfly larvae. They will also eat fish, tadpoles, mayflies, mosquitos, dragonflies, worms, and midges.

Suddenly, the dipper dives into the cold, rushing stream. The bird bobs up and down searching for prey. American dippers are great swimmers and will wade and move small rock as it hunts.

Diving gear

Moments later the dipper pops up very close to the dive location. How can it do that?

Dipper species have their own built in ‘diving gear.’ They have an extra eyelid membrane that allows the bird to see underwater. In addition, the bird can also close off the nostrils (with special scales) when submerged. Finally, their extra oily feathers may keep them warmer when underwater and help shed water quickly.

Diving makes dippers prey for large trout.

Migration

American Dippers are permanent residents for an area and do not migrate. They will move around an area to take advantage of insect hatches and find unfrozen water. Indicator species typically focus on animals that do not migrate.

Huge Song

Both sexes of this species sing an elaborate song year around. The song includes high whistles and trills that can be heard above the chaotic rushing water.

Nests

The American dipper builds an interesting rounded nest as well. The globe-shaped nest is built by male and female birds. It usually on or near a rock ledge, river bank, under a bridge, or even behind a waterfall.  The nest will usually have a side entrance near the water.

The birds dip grass and other materials into water before adding them to the nest. The outer mossy layer is 8-10 inches in diameter and absorbs moisture. Coarse grass helps keep the inside 2-3 inch in diameter chamber dry. The inside chamber also includes leaves and bark.  The female typically incubates 2-4 white eggs. The male helps to feed the young which fledge in about six weeks. Streamside territories are fiercely defended.

REFERENCES:
–Oregon Department of Fish and Wildlife (https://www.myodfw.com)
–Wikipedia, American dipper (https://en.wikipedia.org/wiki/American_dipper)
–All About Birds, American dipper (https://www.allaboutbirds.org/guide/American_Dipper/)

Canada Goose (Branta canadensis)

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It is hard to imagine the familiar Canada goose population in danger. But, in the past, Canada geese were almost wiped out in North America.

The population has rebounded to the point where Canada geese are Oregon’s most familiar bird. For some, they have become Oregon’s most familiar nuisance.

Canada Goose with goslings,
courtesy ODFW.

Not All the Same

There are 11 subspecies of Canada goose that vary in size and color. All have the same long, black neck and white chinstrap. Five of those species are available for harvest (See Oregon Dept. of Fish and Wildlife for permit information.)

Territory & Habitat

Like other swans, ducks and geese, Canada’s are found on every continent and are common to Oregon. They congregate near water, such as reservoirs, lakes, ponds, large rivers, and native wetlands. They have overrun most Eastern native wetlands, including the National Wildlife Refuges created to protect the migratory populations and diversity.

In the past, most Canada Geese migrated to central and southern North America. Now more are resident and live in or near humans year around. The US FWS report that resident birds cause the most problems. Resident and migratory populations have separate breeding ranges and do not typically interbreed.

Diet

Canada Geese are one of the few bird species that can digest grass and primarily eat green vegetation. They also eat aquatic plants and grains, and fish and insects and will pick food off of the street and out of garbage cans.

They have become a serious pest parks, golf courses, farm fields, and airports. Not only can they damage crops but also foul pastures with waste. In addition to farm damage they provoke public nuisance complaints which the U.S. Fish and Wildlife Service (FWS) says are increasing every year.

Raising Young

Goslings (or baby geese) are raised near water. Parents lead goslings to water shortly after being born (great photo opportunities!). After just one day the goslings can dive up to 40 feet under water for food. Goslings can dive or swim away to escape predators.

Canada Geese have oily feathers making them well adapted to swimming, floating, and diving.

Adults aggressively protect their young and will attack anything, including humans, that they perceive as a threat. These are large birds that can be up to 20 pounds, stand 30 to 45 inches, and have a wingspan up to 75 inches). Aggressive behavior can include vocalization, hissing, biting, chasing, and more.

When goslings have learned to fly and the parents have finished molting, the whole family will leave the nesting grounds and find more productive feeding areas. This usually occurs in the late summer before massive southward migrations begin.

Conflicts & Solutions

Sometimes these inappropriate feeding areas are near airports. The Federal Aviation Administration (FAA) estimates there are 240 goose-aircraft collisions annually nationwide. Remember the 2009 US Airways flight 1549 that went down in the Hudson River? It was also traced to migratory birds.

Canada Geese are a protected species under the Migratory Bird Treaty Act.  A variety of management techniques may help deter the geese. Preventing public feeding, altering habitat, hazing, and other techniques have helped. Evidently, floating a silhouette of a nesting swan will deter the geese from an area.

Want more? See any of the excellent resources below.

REFERENCES:
–Oregon Dept. of Fish & Wildlife (https://myodfw.com/wildlife-viewing/species/swans-ducks-and-geese and https://myodfw.com/game-bird-hunting/species/geese)
–All About Birds (https://www.allaboutbirds.org/news/canada-goose-resident-vs-migratory/)
–American Expedition! (https://forum.americanexpedition.us/canada-goose-information-facts-photos-and-artwork)
–Why do migrating Canada Geese sometimes fly in the “wrong” direction? (https://www.allaboutbirds.org/news/i-thought-geese-migrated-south-in-the-winter-and-north-in-the-summer-why-did-i-just-see-a-flock-of-canada-geese-flying-in-the-wrong-direction/
–Wikipedia, Canada Goose (https://en.wikipedia.org/wiki/Canada_goose)

Gaper Clam (aka Horseneck Clam)

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“There were times over the years when life was not easy, but if you’re working a few hours a day and you’ve got a good book to read, and you can go outside to the beach and dig for clams, you’re okay.”
~ Mary Oliver

Oregon estuaries have a rich assortment of clams. Some in great abundance, some with great taste, and some are just watching for your shovel.  

Gaps in clams.
The Gaper clam is on the bottom. (Image courtesy of ODFW)

Why go out and harvest? Think clam chowder, fried clams, clam burgers, and more. Clam chowder is an American favorite and was first serve up in the New England area in the 1700s.  

Two species of Tresus gaper clams are found in Oregon: Pacific gaper clam – T. nuttallii and the Fat gaper clam – T.  capax.

Range

Pacific gaper clams range from Baja California north to Kodiak Island. They are the largest common bay clam in Oregon and California.

In Oregon, the shells may measure up to eight inches long, and weigh up to four pounds. In California they can grow up to 10 inches and weigh up to five pounds each.

Mind the Gap

The clams have evolved in such a way that the shell is just a wee bit small. There is just not enough room to totally retrack the large siphon, or neck, in. This creates a gap that cannot completely close.

Both species of Gaper clams and geoduck clams have this problem. The geoducks have larger siphons compared to the Tresus species.

The siphon is one of the reasons this clam thrives. The siphon filters the water for plankton and bits of food during high tide.

It also helps the Gapers avoid many predators as the clam is able to live deep in the substrate (like potentially four feet). In Oregon, the typical depth for finding Gapers is 12 to 16-inches. Trophy-sized catches are found a bit deeper nearer to 30 inches.

These clams are often incidentally taken during harvest along with butter and littleneck clams that live at the same substrate level.   

Shells

Shells are oval and typically are chalky-white or light yellow. The shell may also be darkly stained in a muddy areas. There are patches of brown, leather-like skin on the shell.

The upper shell is whitish with a thin brown membrane coating. It is relatively thin and can be broken during the digging process. Broken clams count towards daily limit. (See Regulations)

The thickest part of the shell is a cavity called a ‘chondrophore.’ In gaper clams, it is very pronounced. As the shell deteriorates, the chondrophore is the last piece to go. It is often polished by sand and surf and found by beach combers.

Annual lines on the chondrophore’s surface are used to age the clam. Gapers grow about one inch per year for the first four years. Growth rate begins to slow after that. They have a life span up to 17 years.

Reproduction

These animals are quite prolific and, depending on the conditions, may reproduce year-around. Young are carried by the water and swim freely until they settle onto the sea floor. They move downward into the sediments.

Where Found and Harvest Tools

Large bay clams are found on firm, sandy or muddy areas. In muddy areas, clammers often use a shovel or shrimp gun. They look for an oblong “show” hole about the size of a quarter. Some use a three-foot PVC pipe about 12-15 inches in diameter to prevent holes from caving in.

They Got Crabs

You may notice a pair of small crabs (Gaper pea crabs, Pinnixa faba) hanging out with the Gaper.  They are ‘room mates’ and the female may live within the mantle cavity. They do not affect the clam as food.

Lucky Us

Gaper clams are great eating and are fun to harvest. Before you go check the Oregon biotoxin hotline at 1-800-448-2474 and read more at https://myodfw.com/articles/shellfish-and-biotoxins and https://www.oregon.gov/ODA/programs/FoodSafety/Shellfish/Pages/ShellfishClosures.aspx. Always check harvest regulations and requirements.  

NOTE: In certain conditions, you can rebury a Gaper. Leaving it on the surface is a sure death. The Gaper needs the pressure of the surrounding sand to remain intact and maneuver.

Go forth, dig and be Okay!

REFERENCES:
–Oregon Dept. of Fish & Wildlife, Crabbing and Clamming (https://myodfw.com/crabbing-clamming/species/clams and …/species/gapers.html)
–Washington Dept. of Fish & Wildlife, Gapers  (https://www.dfw.state.or.us/MRP/shellfish/bayclams/about_gapers.asp and bayclams/cleaning_gapers.asp)
–California Dept. of Fish & Wildlife (https://cdfwmarine.wordpress.com/2015/06/05/creature-feature-gaper-clams/)
–Sole soups, History of Clam Chowder (https://solesoups.com/2018/02/12/history-clam-chowder)
–Wikipedia, Tresus (https://en.wikipedia.org/wiki/Tresus)
–Mary Oliver quote (www.azquotes.com/quotes)