Monday, January 05, 2009

Survival of the Scrawny?

Annie H sent this Newsweek item about how hunters are trashing the evolution of prey species. I call agenda- driven cherry- picking bullshit. The thesis seems to be that trophy hunting removes all good males and big individuals from the gene pool. This might well be possible in some individual populations especially if it were the ONLY driver of selection.

But: in many areas, from Texas to Scotland and Germany, herds are managed for BIGGER trophies, in the last two for centuries.

In some areas I believe sheep are now manipulated, by seasons and tags, for the same thing. No place in North America (and none in Asia that I know) has open unlimited sheep seasons-- it is hard to get any permit unless you live in Yukon or Alaska, and hard to hunt there.

More hunters are meat than head hunters by far.

There are more trophy elk and mule deer, in the southwest at least, than ever. I have seen more than one record head in the last few years here, and what may be the biggest elk ever was taken on a friend's ranch last year. In most trophy states-- Colorado's "open public" hunt may be an exception-- there is more demand for tags than tags, and elk are expanding in range and huge. Game departments aren't that susceptible to hunter pressure at least in states like NM and Montana that base their take on science.

Kangaroo poachers? Most Australian states list them as vermin or commercial quarry and have no limits-- which may well be bad but has nothing to do with trophy hunting.

There is very little trophy elephant hunting today and most of it is to manage populations. Elephants are victims of an ongoing tragedy based on conflict with human populations but legal hunting is the least of their problems.


M.L. Miller said...

This is a common argument among anti-hunters: That hunting removes the most fit big game animals from the herd.

You are exactly right that this is cherry picking. It ignores much research and many well-documented examples where this is just not so.

Despite a tremendous increase in interest in whitetail trophy hunting, has there been a real decline in large whitetail deer? No.

Texas is perhaps not the best example because many ranches there are bringing in large breeding stock, raising large bucks in controlled conditions and even cloning trophy animals. That is livestock breeding and doesn't have much relevance for wild herd management.

However, trophy hunting in general has been shown to NOT decrease animal size, but instead INCREASE animal size.

Take Pennsylvania. For decades, this state has had a hunting culture that has no value on trophy hunting. Twenty years ago, if you drove across the rural center of the state, you would see meat pole after meat pole with nothing but spikes and forkhorns.

The average age of buck killed during this time was 1.5 years old. No bucks were surviving to old age. This was not due to trophy hunting, but rather killing any buck that walked past.

Biologist Gary Alt instituted a law where bucks had to have at least 3-points on one side, protecting small, young deer. Since then, trophy size has increased.

If you let young male deer (or other ungulates) survive, many will be wary enough to elude hunters when they are larger.

The same is true with elk--elk are not smaller because of trophy hunting, but rather the opposite. It is because so many young bulls are killed.

The Quality Deer Management program used for whitetail management in many states is sound biology. It stresses killing lots of does and only mature bucks. This still allows many bucks to reach maturity.

In some states, like Wisconsin, hunters must shoot a doe before they can take a buck--a great rule. Valerius Geist has suggested that hunters take a certain number of fawns before they can receive a buck tag. Another good idea--but not at all against trophy hunting.

The red kangaroo info is just ridiculous, especially for anyone who has been there.

There are some really unappealing (to me) aspects to the "trophy hunting industry", but one of them is NOT scrawnier animals. This is apparent to anyone who has read the literature and has spent time afield.

Anonymous said...

My experience observing hunters and their effects every year has convinced me that the success and competence of modern hunters afield in this country is NO threat to any game species! Any Whitetail buck that gets old enough to have a big rack is usually wise enough to evade all but the very best hunters, and does plenty of breeding his characteristics before he makes a mistake or dies of old age related problems. I'm not a supporter of trophy hunting myself, but there is little doubt that an effort is made to get the larger males, which are often older and well-past their prime, and done conscientiously, has little impact on animal populations. And pumps lots of money into local economies, therefore making the animals valuable assets to preserve by the local human population. I get irritated with the influx of idiot hunters in my local woods every deer season, and have to strictly curtail I and my dogs' movements till the season is over, but if it wasn't for them, there would be no woods--it would likely all be housing developments!....L.B.

LabRat said...

From a strict population genetics perspective, it boggles my mind that people are seriously making the argument that an emphasis on taking the oldest breeding adults that are monopolizing females is a bad thing for the species.

What, only five percent of males aren't genetic disasters?

Moro Rogers said...

Eventually, deer will become smaller, have more pimples, and grow plastic-rimmed glasses instead of antlers.

Peculiar said...

I think we need an illustration, Moro!

stevea said...

Newsweek is useless.

I would suspect that Dr Festa-Bianchet may have found himself involved in another fluffy interview with Newsweek like this one about the LHC.

I wonder about the real context of his message, aside from the political ideology of the article's author.

Anybody know anything about this guy?

Peculiar said...

I'll wager this bull duplicated a lot of genes before going down in history:

Boone and Crockett Club Confirms New World Record Elk

John Scanlon FCD said...

Nature this week (22 Jan) has a short piece titled 'Run rabbit run', citing an article in PNAS 106, 952–954 (2009) to the effect that
"Predation by humans drives changes in exploited prey much faster than other evolutionary pressures do... In a meta-analysis of work on the morphology and life histories of 29 species, including fish, mammals and plants, Chris Darimont of the University of California, Santa Cruz and his
colleagues found that changes in human harvested systems occurred more than 300% faster than in natural systems, and 50% faster
than in systems affected by other human influences, such as pollution.
The authors suggest that human predation works so quickly because it is often felt by large proportions of the adults in populations."

The direction of selection in any particular system is another matter, of course.

Steve Bodio said...

Dr Valerius Geist has just sent me some papers on this which seem to support Matt Miller's views. I'll post ASAP.