Abstracts of Papers
Diamondback Terrapin (Malaclemys terrapin)
Rozalind Herlands, Roger Wood, Jennifer Pritchard, Heather Clapp, and Norman Le Furge
As part of a long-term research and conservation project on northern diamondback terrapins, Malaclemys terrapin terrapin, we recovered eggs from road-killed females during the 5 to 6 week nesting season every June and July since 1989. Round-the-clock patrols on roads crossing and adjacent to salt marshes on the Cape May Peninsula collected up to 900 eggs each season. The eggs were labeled by clutch,weighed and their lengths measured;they were incubated on moist, very coarse vermiculite in large plastic containers. We maintained the eggs under controlled temperatures,ranging from 26°C to 32°C,in the laboratory facilities at Richard Stockton College. Hatchlings emerged in 7 to 10 weeks. They were tagged and weighed and their carapace and plastron lengths measured. Hatchlings were then head-started in our special terrapin farm until the following summer when they were released into their salt marsh habitat. Our goal was to offset partially the severe mortality of adult terrapins resulting from road kills and from drowning in commercial crab traps. These efforts have provided data on the correlation of egg mass with initial hatchling mass and of incubation temperature with hatchling sex and growth. Initial hatchling mass and incubation temperature seemed to influence post-hatchling growth and development;however,other variables in our terrapin farm,such as tank position relative to heat vents and composition of tank occupants may also have been important. Egg mass varied in any given year. Initial hatchling mass,plastron length and carapace length also varied. Initial hatchling mass ranged between 4 g and 9 g. Higher initial mass was generally greater from larger eggs. Initial mass had the clearest effect on post-hatching growth for the 1996 cohort. Given these data,and in view of our objective of returning as many healthy hatchlings back to the local population as possible,we are working to maximize the birth size of hatchlings. A clear benefit of our project is increased public awareness of the negative impact of human activities on diamondback terrapins in New Jersey. The involvement of local groups in trying to prevent mature females from being killed on coastal roads may have a far greater conservation impact than our recovery and incubation of eggs and the head-starting of the hatchlings.
A Review of Rangewide Regulations
Christina F. Watters
Seventeen years ago, Donnelly et al (1988) complied a summary of regulations pertaining to diamondback terrapins throughout their range. This compilation was never formally published but was widely circulated within the relatively small community of individuals interested in terrapin conservation. Since then, a number of states have modified their terrapin regulations, and an updated and more comprehensive survey of terrapin regulations seems in order. Existing state regulations reflect a widely varying degree of concern about diamondback terrapin conservation. The regulatory status of terrapins varies greatly (State Endangered, State Threatened, Special Concern, Game Animal, no listing). On a federal level, terrapins are not afforded any formal listing or protection. Adjacent states within the range of a specific subspecies sometimes give terrapins different regulatory status listings and manage terrapins with significantly different regulations. It would make sense to coordinate regulatory efforts at least on a regional basis in order to provide more effective protection for this species.
Teaching About Terrapins: Local, Regional,
Christina F. Watters
The Wetlands Institute initiated the Terrapin Conservation Project in 1989 to promote conservation of diamondback terrapins, a species of turtle under severe stress rangewide owing to human activities (habitat destruction, bycatch in commercial crab traps, road mortality). The Institute includes the worlds only exhibit dedicated solely to terrapins, seen by approximately 30,000 visitors annually, including 10,000 school children. The Institute hosts classes, distance learning, and public education programs focused on terrapin life history, research, and conservation activities. The plight of terrapins is publicized by brochures, magazine and newspaper articles, radio and television features, and television documentaries. Another important way of informing and educating large numbers of people is through public lectures as well as participation in community events and regional festivals. The Projects cornerstone program is a summer internship for undergraduate students. During the past 16 years, students from over 90 academic institutions have worked alongside professional researchers and presented their results at regional, national and international scientific meetings. In 2000, the Institute became the host research institution for the Asian Scholar Program. Young Asian herpetologists (10 to date) learn conservation and research skills transferable to wildlife issues in their own countries. Some of our partners include local elementary and high school teachers, Richard Stockton College, Delaware Valley College, the Philadelphia Zoo, the New Jersey State Aquarium, the New Jersey Governors School for the Environment, and the New York Turtle and Tortoise Society.
Terrapins And Traps: The Politics Of Conservation
Roger C. Wood
An estimated 2 million commercial (or Maryland style) crab traps are annually deployed in the coastal waters where diamondback terrapins occur. Large numbers of terrapins drown in these traps (an average of one terrapin in every six traps in our studies). In the early to mid 1990s, research and extensive testing at the Wetlands Institute led to the development of a simple, inexpensive, and highly effective Terrapin Excluder Device (TED) that greatly reduces the numbers of terrapins entering crab traps. In 1998, after two years of highly contentious public hearings, New Jersey adopted a much-amended excluder regulation, which was considerably watered-down from its originally proposed version. Testimony of opponents was often acrimonious. Politics and polemics generally prevailed over rational discourse. Scientific evidence was typically ignored or discounted. Subsequent research has repeatedly shown the effectiveness of terrapin excluders and two other states (Maryland in 1999 and Delaware in 2001) have also adopted excluder regulations. In recent years, it has become increasingly clear that ghost traps are a significant source of terrapin mortality in addition to traps that are in active use. For this reason, TEDs should be required on all crab traps, not just some deployed in specified areas, which is the case for the regulations so far adopted by Delaware, Maryland, and New Jersey.