Box turtle adults are being killed and removed from natural populations at an increasing rate.

Road Mortality
          More road mileage destroys habitat and interrupts turtle travel routes, and increases mortality opportunities.
          More auto travel provides greater opportunity for road crossing mortality
          Greater travel speeds gives less time to react to obstacles and wildlife
          Larger vehicles with more and bigger tires cover a greater proportion of the road surface
          Greater use of in-car technologies encourages less attention outside of vehicle.

Collection from the wild and from roads as pets (removal as pets has the same effect as death)
Habitat, edge, and fence row destruction for construction, aestethics, and for convenience.

Juvenile survival rates necessary for population stability are decreasing
          Female Box turtles lay an average of 4 eggs per year.
          Up to 20% of the eggs may be infertile.
          Embryonic development is often terminated by climatic stresses.
          Predation destroys most or all nests.
          Predation destroys most surviving juveniles under 10 years of age.
          Surviving juveniles need 10 to 17 years before becoming reproductively mature.
          Box turtle predator populations are out of control due to restrictive hunting regulations and few preditors.

The current Land Management approach to Box tutle conservation.
          Waiting for obvious population declines before implementing conservation measures is a dead end strategy.
          Long lived species introduce critical delay lapses in Natural Resource Management response
          The political preference for preserving rapidly reproducing, over-populated Box turtle predators by uneducated,
                 ignorant and uncaring wildlife game and land managers and law makers recognizing no monitary profit in
                 advancing the numbers of non-game species that for which no hunting license or other fees can be assessed.  

         "Lazy" Game Manager and Wildlife Conservation coordination/cooperation is preserving and even increasing
          numbers of wildlife species not in need of protection, and providing little or no protection to species which have
          little economic (tax and license fee) value to sport hunting and fishing.

         The conservation of a species named "Terrapene carolina" is distasteful to politically oriented legislators in
         Virginia who refused to even consider the Eastern Box turtle for the state reptile.



Box Turtles are an Endangered Animal       Peregrine falcons have a life span of 10 years and beginning at 2 years, will produce an annual clutch of 4 eggs, and at 1.5 chicks annual fledge rate, can produce a lifetime maximum juvenile recruitment of 12 adults (minus 30% annual mortality).  In the 1960's and 1970's it was observed that the numbers of peregrines were declining;  adults numbers were in decline and few juveniles were added.    Research found the reason for egg mortality, and mitigation measures were initiated and by the 1990's, numbers of juveniles and adults were on the increase.   If human life span was only 30 years, it would have taken much, much longer for the declining numbers of Peregrines to be recognized, and the species might have gone extinct before it was corrected.

If human life span was 150 years, we would be observing the exact same thing happening to Box turtles, and would be researching and initiating mitigation measures to avoid their numbers declining to extinction.

But we have a life span that is barely long enough to see the number of box turtles around us in decline.  Adult turtles, including many very old adults, are still around.  Their replacements, though, eggs and hatchlings, are not seen because of mortality of adults, and the extremely low survival rate of eggs, hatchlings, and juveniles.


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The Bottom Line
POPULATION MODELING
These models are extremely conservative models.

In the wild, 2:1 sex ratios are common,  many eggs laid are sterile,  populations start with structures containing individuals older than 20 yrs., natural mortality of adults probably starts long before 40 years in most populations.
The Rules of the Game: (pre-assumptions)

All individules are 20 years of age at start.
All females produce 4 viable eggs annually throughout their lives.
The sex ratio starts at 1:1 and stays constant for the life of the model.
There is no outside recruitment.
Old age mortality (natural)  begins at age 40 and doubles at age 60
New recruits are removed from the population at the same rate as the original population.
New recruits add additional recruits at the same rate as the original population.
Mortality and recruitment are percentages, so this model is similar for any size population.

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This Box turtle population is doomed to extinction.

Wth only a small number of females laying an equally small number of eggs per year......
At least 5 of these females cross the highway at least twice per year, and road crossing is probably the most hazardous activity a Box turtle can engage in.

Turtles M1, M4, and M6 are very old and even under the best circumstances, they will only be adding 80 or so eggs each over the rest of their lifetimes. .....their egg adding contribution will be lost to natural mortality.

40 Turtles
0.1% Recrutment  (1 turtle survives out of 1000 eggs)
0.0% Mortality from vehicles
1.0% Initial old age mortality

Turtles are always going to die from old age in natural populations, but excessive predation on eggs and hatchlings dooms the population even without mortality from roads.

The number of 80+ year old turtles in this model is excessive compared to natural populations.
40 Turtles
0.1% Recrutment  (1 turtle survives out of 1000 eggs)
1.0% Mortality from vehicles
1.0% Initial old age mortality

This model adds mortality from vehicles to the above model.  The excessive predation stays, but the removal of adults speeds the demise.
40 Turtles
0.2% Recrutment  (2 turtles out of 1000 eggs)
1.0% Mortality from vehicles
1.0% Initial old age mortality

This model doubles recruitment to the above model.  Adding juveniles to the population does little as long as adults are being removed.
40 Turtles
0.3% Recrutment  (3 turtles out of 1000 eggs)
1.0% Mortality from vehicles
1.0% Initial old age mortality

This model increases recruitment to the above model even more.  The removal of adults is still the major effect on population decline.
40 Turtles
0.8% Recrutment  (8 turtles out of 1000 eggs)
0.0% Mortality from vehicles
1.0% Initial old age mortality

This model adds even more recruitment to the above model, and removes the mortality from cars.  A good share of the population is aged, and still producing juvenile recruitment, but old age mortality, even with this high level of recruitment, still accerates the population toward extinction......it will just take longer.
40 Turtles
0.8% Recrutment  (8 turtles out of 1000 eggs)
1.0% Mortality from vehicles
1.0% Initial old age mortality

This model adds back the mortality from cars.  High juvenile recruitment doen't even begin to replace the mortaility from roads.
40 Turtles
0.8% Recrutment  (8 turtles out of 1000 eggs)
2.0% Mortality from vehicles
1.0% Initial old age mortality

This model doubles mortality from cars to the above model.  Removal of adults from road deaths rapidly dooms this population.  In addition, much of the future population is aged and futher accerates the demise.
Population Modeling
Under Construction
High Elevation Study
 
Raccoons are the number one rabies vector and one of the most destructive wild animals in cities and on farms. Their numbers increase greatly on a cyclic basis, and except for disease, their predators have all but disappeared.

Virginia categorizes the raccoon as a protected game species instead of a varmint, because "it is a native species".  Raccoons, consequently have a very limited hunting season, and because of their little hide value few are killed by hunters.    The only survey of raccoon numbers collected by state wildlife managers, is by "mail carrier survey".   No one knows how large the population of raccoons actually is or how many are removed each year.

The raccoon is the main predator of Box turtle eggs, and can locate egg locations within a day of turtle nesting.  They are likely one of the main predators on hatchlings and small juveniles, also.
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The U.S. Fish and Wildlife Service, a federal agency responsible for the protection of plant and animal species in the United States, primarily deals with the recovery of species with numbers that have already declined to near extinction. This is a very, very, very expensive and inefficient strategy for the protection of any species, and the lack of recognition of decline of species like the Box turtle, that has a very long-lived reproductive strategy, and relatively high mortality rates, dooms the species to future recovery stategies that could have been avoided if initiated earlier

A quote from a press release release from the USFWS concerning the protection status of the Polar bear during climate change, describes it's short term, single-mindedness:   "its biologists had concluded that the [polar bear] was not facing sudden and catastrophic threats and was still a widespread species that had not been retricted to a critically small range or citically low numbers.
The Bottom Line Extinction Conclusion Page is located here
Page 30
Eastern Box Turtle
                Terrapene carolina carolina
A Relict Population Doomed To Extinction?
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