Thursday, September 13, 2012

The Chum are Coming!

Over the past couple weeks, the Sockeye runs have been slowing down. Most of the Sockeye in the spawning areas have now died, and few new Sockeye appear each day. Carcasses litter the streams, ponds, and banks. We've gradually seen less activity on our trail cameras-- fewer bears are visiting key feeding areas, and we come across fewer partially consumed carcasses along bear trails. But the bears have no need to be concerned. There are plenty of other fish in the stream!

Pink salmon are still running, although their numbers have decreased, too. Coho salmon also continue to spawn, but spawn in much lower densities and across larger areas than Sockeye, so it's more difficult to locate their spawning grounds. The bears' next big target, though (and ours, too, for our trail cameras) are the Chum. Just last week, there were only a few fish in this spawning channel off of Herman Creek. Already, the densities are quickly increasing:


Chum salmon are also called Dog and Keta. Keta is the name typically used by canning companies (after all, who wants to eat "chum" anyway?). Chum and Pink salmon are the least commercially valuable fish. Most commercial fishing and canning operations prefer King and Sockeye, but many subsistence fishers in this region like Chum just fine-- especially when smoked, fresh-caught Chum has good flavor.

Chum salmon spawn in autumn, from roughly the end of August through the winter, or at least until the rivers freeze enough to prevent their travel upstream. Chum spawn by the hundreds of thousands, and much like Sockeye they pack themselves into their spawning areas. Chum can pack themselves in even greater densities than the Sockeye. Sockeye are limited by available fry rearing habitat-- once their eggs hatch the young salmon fry need suitable places to grow for a year or two before migrating to sea. Thus, Sockeye need good places to lay their eggs that are also in areas fit for little fish to grow.

Chum, however, are limited only by spawning habitat. Their fry migrate to sea more or less immediately after hatching. Chum salmon don't need to find suitable places for their fry to grow, only good spots for the eggs to hatch. As long as they can locate nice, rocky substrate with good water flow, they can spawn, so Chum find whatever spawning habitat is available, even if there are already hundreds of other fish around. This makes them easy for wildlife to access. Just walk up to the water and grab one!

With the weather quickly cooling and the Chum beginning to run, the eagles are beginning to congregate. We've started to see far more eagles around Haines recently. Gradually over the next month, the water level of the Chilkat River will drop, exposing the river flats and providing many shallow areas for wildlife to access fish. The Chum run will increase, until the braided areas of the Chilkat are packed with fish. And, as temperatures continue to decrease and freezing begins elsewhere along the coast and in the interior, more and more eagles will travel to Haines to feast on Chum through the beginning of winter.

We will continue to set our trail cameras out to capture wildlife feeding on salmon. At the end of this week, we will take down our last set of trail cameras from the Sockeye runs, and, starting next week, will set our cameras on Chum spawning areas and on higher elevation wildlife trails. Once the eagles begin arriving en mass, we will also start working on the second part of our research here-- looking into eagle migratory behavior!

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