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Controlling the Deer Population
in South Mountain Reservation

This is currently a quote of an email that I sent to the West Orange Watercooler. I will update it appropriately as I can.

The following claims were made by a member of that group. I think every one of them is irrelevant, hyperbolic, or seriously misleading, so I rebut them.

Please feel free to leave comments at the bottom of the page.

The County Executive Isn't Listening To The Right People

This is just a series of arguments from authority -- and dubious authorities at that.

Claim:

Irrelevant. Rivielle is the head of "Save Our Wildlife", the group that severely understated the deer population earlier this year. (Web site readers, I'll post evidence of this claim later.) Nina Austenberg has neither the responsibility of County Executive DiVincenzo nor the commitment to the South Mountain Reservation ecosystem as a whole that the South Mountain Conservancy does; and whatever her interests are, they apparently lead her to ignore the basic findings of the USDA NWRC and others.

Claim:

Hyperbolic. Given Rivielle's undercounting of deer, why trust her counting of accidents? The County Executive pays for deer removal after deer-vehicle collisions. He knows how much he pays for.

Claim:

Rivielle has shown herself to be untrustworthy, so I went to the American Lyme Disease Foundation Web site. The only reference to "hunting" that I could find was here. It said:

I have emailed the ALDF for clarification on their position regarding lethal deer population control methods.

Having said all that, the comment is mostly irrelevant, because Lyme Disease is only one of the reasons that we're slaughtering deer.

Claim:

Also, from another post:

Hyperbolic. Shouting "IGNORES" is just marketing spin. DiVincenzo has already proved that his information is more reliable than these studies. As the next item shows, there were 100-120 deer in the reservation AFTER the hunt and BEFORE the fawning season.

Claim:

False, and worthy of ridicule. (Not Sylvia, the person who compiled her list.) Here's the article, and it says:

The Times story says exactly the opposite of what they're trying to prove.

Contraceptives Make The Hunt Unneccessary

Claim:

Also, from the second post:

Highly misleading.

I've looked into the GonaCon contraceptive, and here are relevant bits of what I've learned. Everything I quote here is from one of the documents referenced at the bottom of this email. I'll start with general information that the studies give us, and then move to the specific contraception information.

In a nutshell: based on the research of the USDA's National Wildlife Research Center, the GonaCon contraceptive (a) would require us to kill between 1/3 and 2/3 of the deer before we administer it, and (b) would still require us to slaughter or cull deer every few years.

I don't know who is telling people that this contraceptive can eliminate lethal methods of controlling the herd, but they're feeding us a line. The study for GonaCon comes with the statement "It must be emphasized that wildlife contraception using GonaCon™ vaccine and other infertility agents will not replace sport hunting as a wildlife population management tool." And even more bluntly, the GonaCon FAQ itself says this:

General info

Each of the following is backed up by studies cited in the sources.

First, it's pretty common for deer to be overpopulated in a given area. "According to a recent estimate, white-tailed deer are 'ecologically excessive' (i.e., they exceed biological carrying capacity) on 73% of the species' range in North America."

Second, hunting (sport hunting or more deliberate slaughters) seems to be the primary way that deer populations are kept in check. One statement was, "In most parts of the country, hunting remains the most effective and efficient means of controlling deer."

Third, capture-and-relocate programs don't work very well. "Survivorship of translocated deer has typically been very low, with transplanted deer being killed by hunters and collisions with vehicles at much higher rates than those of “resident” deer at the release sites. Translocated deer also tend to cause the same problems in their new environments as they did in their old ones, because they seek out residential neighborhoods where they have learned that they can find food, water, and shelter. In addition, many state wildlife management agencies no longer permit translocation of deer because of concerns related to disease transmission among deer." (References omitted.)

It's worth noting that the only problems mentioned with our current type of program were cost and "public relations nightmares" caused by "public opposition to lethal control of deer and perceived threats to human safety."

Contraception info

The first step in a contraception program is to thin the herd to appropriate levels. Yes, that means slaughter them. "Several years ago, an environmental assessment (EA) of deer management determined that the preferred management alternative was to cull the herd and then implement a deer contraception program. The EA recognized that applying contraception to a severely overpopulated herd without first reducing deer numbers to a desired level was not an effective way to reduce population size. Accordingly, during October 2003, 214 deer were removed from White Oak by wildlife professionals from the Maryland office of USDA APHIS Wildlife Services through nighttime sharpshooting."

To me, this says that even if the contraceptive were on the market right now, we'd still need to go ahead with the deer slaughter. We'd need to kill something between 1/3 and 2/3 of the number of deer in the area. Sylvia has said that "studies show" that there are only 50 deer in the reservation now, but as I have pointed out, those studies apparently seriously undercounted before the last slaughter, so I'll go with the County Executive's imperfect, but more reliable, numbers.

The sample size was pretty small, and there are some uncertainties in the way the fawns were counted, but here are some bottom-line numbers: with the contraceptive, 12% of the does had fawns; without the contraceptive, 85% of the does had fawns. That what they mean in the study when they say that the contraceptive was 86% effective.

One important note: twins are common among deer, and even triplets aren't unknown. The study was unable to ascertain how many multiple births there were. The numbers that follow pretend that there were only single births.

That's not the end of what we can extract from this, though. First, note that 85% of untreated does had fawns. If we take the County's lower estimate of deer in the reservation this year and assume it's about 87, and half of those are does, we can expect 87+(87/2)*.85 = 124 deer the next year. (I'm overcounting by ignoring the mortality rate. I'm undercounting by ignoring (a) births from this year and (b) the twinning rate. I have no idea what any of these rates are.) This is explosive population growth. It answers the question, "Why don't we just let it go for a year?"

Even with the contraceptive, however, the fawning rate is about 12% per year. That means that even if they were contracepted today (which they can't be) there would be 87+(87/2)*.12 = 92 deer in the reservation next year -- still 50% over what the County's experts say there should be.

Even if we further low-ball the initial count to the studies that the anti-slaughter folks have used (50 deer in the reservation now) AND contracepted them today (which we can't) we would require a hunt no later than 2011, because there would be 70 deer in the reservation.

My conclusion: even if the contraceptive is as effective as they say, the County will continue to need to slaughter a lot of deer this year to get the numbers in line, and then continue to kill at least some every year or two to keep the numbers in check.

Resources

GonaCon is being developed by (or in conjunction with, I can't quite tell) the USDA's National Wildlife Research Center in Fort Collins, CO. They're trying to get it registered with the EPA as a wildlife contraceptive agent. I could find no information on when it might actually be released to the market. The Web page to see is here.

Here is a list of publications about reproduction control.

The one I quoted from most is here, called "Field Test of GonaCon Immunocontraceptive Vaccine in Free-Ranging Female White-Tailed Deer".

The County Executive And Others Are Political Operators Who Do Bad Things

Claim:

Egregiously misleading. Lying, even. (Again, I'm not accusing Sylvia of lying, but I am accusing the people who made her list of doing so.)

This makes it sound like That Evil Man DiVincenzo COULD use nonlethal methods, but wants to kill deer instead. That's just false. Here's one example of him using nonlethal control methods.

Claim:

Don't know. Likely hyperbolic at least. Given what I know of this list so far, I'd like to get the SMC's side of the story. At any rate, the SMC is certainly not an enemy of deer.

Claim:

Irrelevant and misleading. The SMC volunteers do a ton of work in the reservation for free. If anyone wants to join them in caring for the reservation, contact Andrew Joyce at amojoyce -a-t- aol.com. He personally gives up a lot of his weekend time to do cleanups and other reservation activities.

Since the SMC does so much work to help maintain county property, I'd say that Essex County's partnership with them is a good example of civil / citizen organization partnership. Half a million might not be as much as they deserve.

Claim:

Irrelevant. You can't on the one hand complain that Essex County doesn't listen to advice, and on the other complain that they hire advisors. Unless you can show that Daniel Bernier is untrustworthy, this is simply a political smear.

Claim:

Probably true, though I haven't seen it. I would prefer to see a slaughter instead of a hunt, but DiVincenzo has to do something.

The Slaughter Won't Solve The Real Problem

This set of claims presupposes that if we don't solve everything, then we've solved nothing.

Claim:

False AND irrelevant. The disastrous effects of deer overpopulation are well-documented by the USDA NWRC.

It is irrelevant that other things also despoil the land. If you have cotton-soaked gasoline, both the cotton and the gasoline burn -- but the gasoline is burning much hotter and is much more dangerous.

Claim:

Irrelevant and misleading. First, because we know that if we don't thin the deer, the vegetation will not come back. Second, because we can be reasonbly confident that with a slaughter of deer and with proper nurturing, the ecosystem will rebound. Third, because DiVincenzo has committed to creating a plan to manage the reservation's recovery. The fact that this is not yet defined doesn't mean that it won't be.

Claim:

Irrelevant. If the town council had done their research on this, they would have discovered that hunting or slaughtering is the most efficient and effective method of controlling the herd, and that most of the anti-slaughter arguments don't hold up to basic research.

The Slaughter Is Cruel

Most of these claims were irrelevant, because even if they're true we still need to slaughter deer. Also, in every case but two, our methods are much preferable to the methods that nature would use.

There was a lot of SHOUTING in this section that I have normalized.

Claim:

And

Age doesn't matter in this case. Normally you avoid killing fawns because you want to avoid having an old population, but that doesn't apply here. More below.

Claim:

Irrelevant. Single-gunshot kills are only common on TV.

Claim:

Hyperbolic. Running "out of sight" doesn't mean they went far -- maybe just over a ridge. If only five were tracked (see below), then they didn't run far.

Claim:

Irrelevant. When you're definitely killing something, an extra shot can be a kindness.

Claim:

Irrelvant and hyperbolic. This statistic means that 85% of deer died relatively quickly, before they went far.

Even among the 15% that were tracked, this is not worse than being hunted by their natural predators.

Claim:

Probably about right, but irrelevant. Our sharpshooters had a 98% kill recovery rate. Though unfortunate, I forgive the 2%.

Claim:

Unfortunate, but irrelevant. Yes, I'd like to prevent this kind of thing from happening. In the latter case, this isn't a problem with the shooter, but with an off-the-leash pit bull.

Claim:

Likely true, but irrelevant. If I understand correctly, the men wounded the deer and were trying to finish it, and were unable to make it go down before it entered a residential area. Once it enters a residential area, the hunters should not be shooting at it.

Deer would be less likely to go into Millburn back yards if the South Mountain Reservation were healthier and they had less reason to graze outside of it.

The Slaughter Violated Procedure

Claim:

Here is the 2008 Deer Management Program.

This claim is misleading and hyperbolic, for at least two reasons.

First, it's misleading because "during daylight hours" doesn't mean "between sunrise and sunset". Civil twilight, the time just after the sun goes down but before it gets dark, is also daylight. On January 31, 2008 civil twilight ended at 5:42 PM. On February 21 it ended at 6:06 PM. You can verify these facts here.

Second, it's hyperbolic because killing these deer after daylight wouldn't have been illegal anyway. These are guidelines for this slaughter, but if Divincenzo decided to kill deer after dark, he could. The GonaCon contraceptive people slaughtered their herd after dark, for instance. Our sharpshooters were allowed to stay in the reservation until 8:00 PM.

I say "at least" two reasons because who knows what the time means? Was this the time that the deer was initially shot, or the time that it was "finished", or when it was retrieved, or what?

Conclusion

I did not start off being pro-slaughter, though I'm not against the idea of non-lethal methods if they'll do the trick. After doing the research necessitated by the anti-slaughter contingent, however, I have yet to see a single anti-slaughter argument that stands up to examination. I therefore come out in favor of slaughtering deer to bring the herd back to a reasonable level.

By the way, based on this fact, I hearby announce my support for Robert Parisi and Patty Spango for West Orange Town Council during their next reelection cycle. I also place myself solidly against Susan McCartney, Sal Anderton, and Renard Barnes for voting against the "hunt". If they had done their research, they would have known that their vote would encourage people to think that there are options available to DiVincenzo when there are not.