Monday, September 19, 2022

Managing Alaska's Game Populations

For certain game populations, a quicker response is needed.

There are many factors involved in managing game populations. The Alaska Department of Fish and Game is saddled with that task. In discussing the subject with a biologist, numbers and studies will rule the conversation. Are numbers really the crux of management? (...)

Take a look at Nelchina caribou management. The goal is 35,000 critters, give or take. Harvest 5,000 caribou, replace the 5,000. That sounds easy.

However, to replace the desired animals we need to determine a few variables. What is our optimum bull/cow ratio? How many bulls will the hunters get? How many will the wolves get? What will the winter kill be? These factors cause things to get a little dicey.

Let’s complicate management a bit more. How much snow will we get this winter? Will it melt early enough for the cows to reach the calving grounds? High rivers or a rainy summer might cause excessive mortality on young caribou, thus affecting projected recruitment.

Biologists must also factor in how many Nelchina caribou join the 40-Mile caribou herd. The two herds have wintering grounds in common. Nelchina caribou wintered from Mount Sanford all of the way to Dawson last season. Did some join the Porcupine herd? Fish and Game says it doesn’t think so.

How many caribou taken in the 40-Mile hunt might have been Nelchina animals? The 40-Mile seasons have been quite liberal the past few years. We do know that the 2022 Nelchina population estimate is now on the low side of 21,000 animals. This is down from the estimate of 35,000-40,000 animals a year ago. That’s around 15,000 missing animals.

There is an estimate of a 10% loss of Nelchina caribou into the 40-Mile herd. This is based on two out of 20 collared cows. Small sample. The winter kill estimate that 30% of the cows did not survive is based on the same sample.

However, the population of the 40-Mile herd is also down. The 40,000 population estimate is down considerably from the estimate of several years ago. In addition to interacting with the Nelchina herd, the 40-Mile animals also may cross paths with the Porcupine herd, though that is an unknown at this time.

The population estimate on the Porcupine Herd is very rough at this time. That herd ranges well into Canada. The winter range certainly intersects both that of the 40-Mile and Nelchina herds, at least last winter.

Browse availability must also be considered. Caribou feed primarily on wheat grass and lichens during the winter months. Summer feed is similar with the addition of some seasonal plants such as fireweed, dwarf birch and willow. What does the status of available browse need to be to have a happy, returning caribou herd? Nobody knows that. There may be some older reindeer herders who have an anecdotal handle on that, but who talks to them?

As you can see, very few of the factors affecting proliferation of caribou are predictable or controllable.

The only guarantees are politics and regulation. There are many special interest groups who wish to shoot at a caribou. Some want them for food. For others the priority is the hunt itself. There are five separate permit hunts for Nelchina caribou. There is also a community hunt and a federal subsistence hunt. The details of these hunts are not important. What is important is the various groups that have lobbied and harassed successfully for these hunts. This is politics — not biology.

by John Schandelmeier, Anchorage Daily News |  Read more:
Image: Dean Biggins, USFWS, Creative Commons
[ed. See also: Nelchina Caribou News (pdf) - Alaska Dept. Fish and Game.]