Being a math geek allows one to see the sleight of hand in many overly burdensome management schemes, because often the abuse of power is buried in flawed analysis and complex population models and is not directly demonstrated in the data. Many stakeholders in wildlife management are left merely trusting or distrusting the "scientists" because they cannot unravel the complex models. For example, the Roy Crabtree and James Cowan crowd based the overly restrictive red snapper regulations on complex Gulf of Mexico wide population models. In contrast Bob Shipp and LDWF take a more local and more directly data driven approach that makes it obvious that red snapper populations would support higher harvest levels in certain waters.
One can develop complex population models for deer too, but there can be a lot of insight based more directly on data. For example, in a Parish where the deer herd is close to its carrying capacity with a balanced (near 50/50) sex ratio and being managed both for sustainability and near maximum hunter success rates, about 1/3 of the deer population can be safely harvested each year. Let's take a hypothetical parish with 3000 deer. The "brown is down" management approach will yield (on average) 1000 deer per year, assuming negligible predator and collision mortality rates. Average collision and predator mortality rates of 100 deer per year would leave only 900 deer for the hunters.
In contrast, depending on the implementation details, most QDM or big bucks management schemes allow for only 10-20% of the population to be harvested each year (depending on the details). Antler restrictions requiring 4 pts on a side would probably allow 20% harvest, or 600 deer per year in a parish with a carrying capacity of 3000 deer. This is because QDM changes the age and sex structure in the population with more older deer and fewer bucks. The average age at harvest would shift from between 1.5 and 2.0 years up to 2.0-4.0 years, and the percentage of does would shift from 50% or so down to 20-30%.
This is very similar to a cattle ranch that can produce 500 beef cattle per year if they are harvested at an age of 1.5 years, but would decrease in production to 300 cattle per year if shifting to a harvest age of 3 years.
The numbers are approximate, but the idea that increasing the average age at harvest will always reduce the available harvest for a given carrying capacity is very sound.
Management can take an alternate approach through improving habitat (carrying capacity) and reducing losses to predators and other non-harvest mortality (collisions dominate in deer). This would enable a given system to produce both more trophies and more younger animals for harvest. In deer, this can be planting and maintaining food plots, increasing edge, etc. Even keeping an area mowed (with a brush hog) once or twice a year rather than grown up can provide a lot more forage. Assisting in efforts to control wild hogs and coyotes can reduce predation and habitat destruction.
In seatrout, habitat restoration can do a lot more than more restrictive limits. Oyster reefs and marsh are key. Most natural predators are reasonably well controlled, and killing more sharks or dolphins is unreasonable since both of these are well below historical levels. Saltwater intrusion is the biggest threat to the marsh, and overharvesting of oysters and depredation by black drum are the biggest ongoing threats to essential oyster reef habitat. Killing every black drum you catch (within legal limits) probably does more for seatrout than killing every coyote and wild hog you see does for deer.
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