Wednesday, September 24, 2014

River Otters Feast on Salmon at Capitol Lake

By Nancy Partlow 

Text in Red Bold is a clickable link to video.

A family of river otters has been putting on quite a show at Capitol Lake recently.  They've been catching and eating Chinook salmon in full view of the public. 

Janet’s friend Cynthia told her she’d seen a mother otter and three pups chomping on salmon near the train trestle at Marathon Park.  We decided we  had to check it out.  Unfortunately, when we got there, no otters could be seen. 

So the next day, on a hunch, I decided to peruse the area along the lake near the 5th Avenue dam.  A few years ago we had seen otters in this vicinity in late November.   Sure enough, as I walked along the lakeshore, through the shrubbery I spied two otters slither off a log and move out into the lake.  As I entered Heritage Park, out in the middle of the north basin, five heads were just discernible poking above the water.

I began to film them.  So intently was I watching three otters masticating salmon that I only slowly became aware of people nearby saying things like, “Oh, look, it’s got a salmon head!”  Turning around, I was very surprised to see a mother otter and her pup on a log in the water about 15 feet away.  The mother had a salmon head she was biting into with obvious relish.  The look on the face of the salmon was one of astonishment with perhaps a touch of, “I came so far, was so near my goal, and then this!”

The Chinook salmon in the lake are following the fresh-water scents of their natal streams, the Deschutes River and Percival Creek, to their long journey’s end.  But for some, the odyssey terminates just short of "home".  For years, we have watched harbor seals corral and devour salmon on the north side of the 5th Avenue dam, which forms a bottleneck and gauntlet through which the salmon must pass before entering the lake.  It never occurred to us that the waters on other side of the dam could also be a kill zone.  For one thing, we didn’t think that river otters could catch and dispatch something as large as a king salmon, which may be as big, (or bigger), than the otter itself.  But according the WA Department of Fish and Wildlife’s page on river otters, they do eat salmon, among many other prey items:

River otters are opportunists, eating a wide variety of food items, but mostly fish. River otters usually feed on 4- to 6-inch long, slowly moving fish species, such as carp, mud minnows, stickle backs, and suckers. However, otters actively seek out spawning salmon and will travel far to take advantage of a salmon run. 

River otters can smell concentrations of fish in upstream ponds that drain into small, slow moving creeks, and will follow the smell to its origin, even in urban areas.
River otters also eat freshwater mussels, crabs, crayfish, amphibians, large aquatic beetles, birds (primarily injured or molting ducks and geese), bird eggs, fish eggs, and small mammals (muskrats, mice, young beavers).

Salmon heads must be a particular delicacy, because the mother otter didn’t want to share it with her pup.  In surveying the whole scene, I surmised that perhaps the mother had killed the salmon, bit off the head, then left the kids (most of them, anyway) out in the middle of lake to eat the body while she came near shore to nosh on the best part in relative peace.

The two otters on the log seemed not at all perturbed by the small group of humans watching them from a few feet away on the bulkhead.

A couple of folks thought the otters might be nutria, which are an invasive species in the lake.  But nutrias are vegetarians.  One woman said, “What a blessing!”, about being able to watch the mother and pup so close-up. Another man related a story of how, many years ago in front of Genoa’s restaurant (now the Hearthfire), he had seen two otters mating very loudly.

According to WA DFW, “River otters digest and metabolize food so quickly that food passes through their intestines within an hour.”  This could explain why, when I returned a few hours later, the otters were still hunting and eating, with  four otters now on the half-submerged log.

I couldn’t tell whether the mother was among them, although one was again eating a fish head. Three of the otters were playing and nuzzling each other. 

When the trio swam off together, the fish eater didn’t want to follow, only reluctantly diving into the water with the salmon head in tow.  Later, as the day moved toward sunset, Janet told me she saw the whole family swimming toward the railroad trestle. 

I had heard an intriguing rumor that river otters had been seen in the fish ladders at Tumwater Falls Park, so I decided to stop by the park on my way home.  I spoke with a DWF employee there, asking if he had seen otters in the fish ladders.  He said he hadn't.   

He did say though, that in the spring when the fish tanks are full of small salmon ready to be released into the river, young otters enter the tanks and eat many of them.  They've tried to block the otters from getting in, but the clever mustelids end up climbing over the chain link fences.

As it turns out, the story about the fish ladders was partially true.  It was referring to the fish ladders at the 5th Avenue dam. Not surprisingly, otters move with ease back and forth through the open dam to access both the fresh and salt waters of the lower Budd Inlet.  That is why the otters are frequently seen at the West Bay lagoon and elsewhere along the Olympia waterfront.

Now that the rains have returned in earnest, opportunities for watching the salmon-eating otters may decrease. A slug of fresh rainwater flowing into the Deschutes River and Percival Creek systems could trigger the salmon to make a final rush to their ultimate objectives.  Such is the cycle of life.  We here at the end of the Salish Sea are indeed blessed to be part of it.

All words, photos and videos by Nancy Partlow ©

Additional video:

Other Resources:

WA Dept. of Fish and Wildlife page on river otters:

1 comment:

  1. Absolutely stunning photography and writing, Nancy, and a consistently beautiful blog, Janet and Glen!

    Each time I receive a post notice, I know I'll want to create the mental space and take time to read and re-read it, because I know it will suck me in. You take me right along with you on your adventures....thank you!

    Your detailed observations of the presence and habits of our local creatures is priceless knowledge.

    Janine Unsoeld