Population Size and Structure of the Ornate Diamondback Terrapin (Malaclemys terrapin macrospilota) on Small Gulf Coast Islands in Florida

2021 ◽  
Vol 20 (2) ◽  
Author(s):  
Eric Suarez ◽  
Travis M. Thomas ◽  
William M. Turner ◽  
Ryan L. Gandy ◽  
Kevin M. Enge ◽  
...  
2019 ◽  
Vol 97 (3) ◽  
pp. 251-257
Author(s):  
Kayleigh Rose Erazmus ◽  
Miranda P. Figueras ◽  
Luca Luiselli ◽  
Russell L. Burke

Animal diets may vary spatially or temporally as resource availability vary. Diets of species with extensive geographic ranges often span multiple habitats, thus their diets may vary accordingly. Temporal diet variation is rarely explored because most diet studies are short term; this is problematic for long-lived species where individuals may persist as prey availability changes. We analyzed diet variation in Diamondback Terrapins (Malaclemys terrapin (Schoepf, 1793)), which inhabits nearly 70 000 km of United States Atlantic coastline, spanning 16.5°N latitude and 27.4°W longitude and four Köppen climatic zones, and Bermuda. We explored spatially or temporally Diamondback Terrapin diet variation, including populations from Atlantic salt marshes, an Everglades mangrove swamp, the Texas Gulf Coast, and a Caribbean golf course pond. We found remarkably high levels of similarity, indicating that although diets vary according to local prey availability, they are broadly similar at lower taxonomic resolution. Even short-term studies may be sufficient to accurately characterize diets of Diamondback Terrapins. These results are surprising given the geographic range sampled in this study and indicate that Diamondback Terrapin diets are conservative, reflecting local prey availability. Such diets apparently allow Diamondback Terrapins to exploit their extensive range and may allow Diamondback terrapin populations to persist as local prey species wax and wane.


1997 ◽  
Vol 31 (3) ◽  
pp. 308-309 ◽  
Author(s):  
Cáris M. Nunes ◽  
Dejanira de A. Martines ◽  
Stélios Fikaris ◽  
Luzia H. Queiróz

Planning control programs, for diseases such as rabies requires information on the size and structure of the dog and cat population. In order to evaluate the dog population of the urban area of Araçatuba city, S. Paulo State, Brazil, a survey was conducted using a questionnaire to interview members of households. Eighty-eight districts were visited (37,778 houses) and the interview was possible at 77.93% of these. Human population size evaluated was 113,157 inhabitants. Houses that owned animals represented 55.2%, 26,926 of the animals concerned were dogs and 5,755 were cats. Of the dogs, 56.64% were 1-4 year olds and males represented 56.2% of the total population. Dog: person ratio was estimated at 2.8 dogs to every 10 persons, almost 3 times the ratio hitherto estimated and used in the planning of rabies vaccination campaigns.


Copeia ◽  
1982 ◽  
Vol 1982 (1) ◽  
pp. 161 ◽  
Author(s):  
Mary T. Mendonça ◽  
Llewellyn M. Ehrhart ◽  
Mary T. Mendonca

2017 ◽  
pp. 65-72
Author(s):  
Z. О. Palian ◽  
I. H. Bondarenko

A balanced change in demographic processes should be considered as a prerequisite and, at the same time, as a result of the stable development of the state. Reproduction intensity depends not only on the character of demographic behavior, but also on the presence of contingents of the population, providing or potentially able to provide for its replacement. The dynamics of Ukrainian population, the transformation of its gender-age structure during the period of independence, taking into account the intensive and structural factors of natural increase and migration, is considered. During 2002-2015, the regime of survival and fertility improved in Ukraine, due to which the depopulation slowed down somewhat. But even these positive changes do not compensate for the loss of population size as a result of systematic aging, reducing the proportion of reproductive contingent and its aging. Significant demographic losses, direct and indirect, were caused by a hybrid war from Russia. Alienation of the territory of the Crimea and parts of Donbas is not only a minus 2.5 million citizens of Ukraine. This is a change in the structure of the population - a decrease in the proportion of older age groups that increase the demographic load and worsen the characteristics of survival and fertility of the maternal generation. In this work are presented the results of the short-term simulation of population size and structure taking into account modern trends of replacements components and existing administrative-territorial changes. Two scenarios of the forecast for 2018 have been developed, and the base year it was taken in 2013, when the Crimea was part of Ukraine. The first, realistic scenario was based on the preservation of the current situation - Ukraine without the annexed Crimea and the occupied part of the Donbas. The second scenario imitates the return to Ukraine of all the lost territories. Simulation showed that the population of Ukraine will be reduced by both scenarios, but to 41.9 million people under the scenario without the occupied and annexed territories and to 44.7 million people in the second scenario. The finish of war will due to slow down the death rate to 14.9%0. The age structure of the population does not differ significantly in two scenarios, because the forecast horizon is very short (4 years). The share of generation of parents and women of reproductive age in both variants of the forecast decreases. However, in the case of returning Crimea, it will be even lower (47.4% vs. 47.5% in the first scenario). The reason for this is the emigration of young and middle-aged people to the mainland of Ukraine and to the Russian Federation, which provided some preferences to the settlers from Ukraine. Expected structural changes combined with the modern life and fertility regime will worsen natural population growth rates in both scenarios. In further research is planned to build trend models of births and deaths that will allow the artificially restore the interrupted time series due to administrative-territorial incomparability of data on demographic events


2008 ◽  
Vol 4 (2) ◽  
pp. 216-219 ◽  
Author(s):  
James F Parham ◽  
Mark E Outerbridge ◽  
Bryan L Stuart ◽  
David B Wingate ◽  
Helmut Erlenkeuser ◽  
...  

Humans have greatly altered the natural distribution of species, making it difficult to distinguish between natural and introduced populations. This is a problem for conservation efforts because native or introduced status can determine whether a species is afforded protection or persecuted as an invasive pest. Holocene colonization events are especially difficult to discern, particularly when the species in question is a naturally good disperser and widely transported by people. In this study, we test the origin of such a species, the diamondback terrapin ( Malaclemys terrapin ), on Bermuda using a combination of palaeontologic (fossil, radiometric and palaeoenvironmental) and genetic data. These lines of evidence support the hypothesis that terrapins are relatively recent (between 3000 and 400 years ago) natural colonizers of Bermuda. The tiny population of Bermudian terrapins represents the second naturally occurring non-marine reptile that still survives on one of the most densely populated and heavily developed oceanic islands in the world. We recommend that they should be given protection as a native species.


1967 ◽  
Vol 46 (1) ◽  
pp. 161-167 ◽  
Author(s):  
P. J. BENTLEY ◽  
W. L. BRETZ ◽  
KNUT SCHMIDT-NIELSEN

1. While in hypertonic environment diamondback terrapins (Malaclemys centrata) slowly lose water by osmosis through the integument and as urine through the kidney. 2. Small amounts of sodium are gained, probably largely as a result of diffusion through the integument rather than by drinking, and this sodium is principally excreted extrarenally. Nevertheless, the solute concentration in the blood of such turtles increases. 3. When returned to fresh water the animals rehydrate and excrete accumulated excess sodium. 4. In these ways they could undoubtedly survive for extended periods in the absence of fresh water, but it is not clear whether they could do so indefinitely.


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