July 10, 2010

High intensity wildlife management: to the rescue of sea turtles

The first few lectures in my Wildlife Ecology and Management course always contain examples of 'indirect' and 'direct' wildlife management. Indirect management is defined as when a manager makes decisions that affect populations indirectly...such as changing water levels for fish or ducks, doing a prescribed burn for grassland birds, or providing winter food for elk. Direct management is when you literally change population sizes directly, and hunting and fishing are oft-used examples. Culling a population of deer is another. Translocating wolves to Yellowstone is an example of increasing population size directly.

It looks like I have another example for my 'direct' management lectures. In one of the largest wildlife management efforts, of which I am aware, the US Fish and Wildlife Service is translocating nests of sea turtles from the Gulf size of Florida to the Atlantic side. 100,000 eggs--from approximately 1,000 nests--will hatch in cooled containers, rather than in sand.

This effort is a good example of the process of assessing risks for a population. Although the translocation has risks (some eggs may not hatch, digging probably will destroy some eggs, etc.), the alternative is judged to be higher risk. That is, leaving the eggs presumably will result in extremely high mortality of hatchlings. However, that is not certain...there is no guarantee that all hatchlings will die if nothing is done. But, the most critical piece of information is that 90% of the sea turtles in the US nest on Florida beaches...so if something bad does happen, it's going to happen to all of the turtles.

So, this is a gamble to save a year-class of hatchlings, who will have to survive until their 30's to come back to these beaches to contribute to the population. I'll be retired by the time we see if this gamble pays off!

No comments:

Post a Comment