[CT Birds] Ruffed grouse
elphick at sbcglobal.net
Sun Mar 10 15:30:33 EDT 2013
Hi Paul et al.,
I have stayed out of the debate about grouse so far as I don't know a great deal about the species in CT. But I do have a couple of comments from the perspective of a population biologist (that is someone who studies changes in population sizes and the things that cause them) and as someone who has been involved in many discussions over many years about how to do conservation effectively here in CT and elsewhere.
>From a population biology point of view, I would say that, although I care very much about the persistence of grouse in the state, I am not too worried about a low level of harvest (I don't know the current rate, but my understanding is that it is relatively low). This may seems counter-intuitive, so I'll try to explain why. Ruffed grouse - like most game birds - have high reproductive rates (lots of young produced per female each year) and naturally high mortality rates (individuals don't live very long). In species with these traits ("r-selected" species in the jargon of the trade) adding some mortality - as long as it is not excessive - rarely has much effect on population size. In other words, the high reproductive rate buffers the population against the high mortality rate. Obviously, if you kill too many then there will be a problem, but in a species like ruffed grouse, that number would probably have to be a pretty high percentage of the
Determining how many is too many is actually not that hard if you know something about reproductive rates and natural (non-hunting) mortality (simple enough that I'll be lecturing on it to my undergraduate class in a couple of weeks), and these calculations are routinely used to set bag limits for hunted species. I've not seen the math for ruffed grouse in CT, but I would only be concerned if those calculations lead to the conclusion that hunting levels are too high.
For species that are long-lived and have low reproductive rates it is a completely different story. Even small increases in mortality can be devastating - this is why most of the world's albatross species are heading towards extinction (something to think about next time you tuck into a swordfish or tuna steak from a longline fishery!).
Now my second point, from a pragmatic conservationist's perspective (and this relates to the point Patrick made). The harsh reality is that much of the money that funds conservation in CT, and elsewhere in the US, comes from hunters. Calls are repeatedly made to the birding community to change that and find an additional revenue stream whereby birders contribute more money to fund the conservation done by state agencies. Many people have worked hard on various initiatives to make that happen, but the sad truth is that so far the birding community has failed. If birders want to change things then that is where the phone calls and energy need to be directed. Money talks, and if we're the ones funding conservation we'll have a lot more say over how it is done.
elphick at sbcglobal.net
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