Adopting turtle excluder devices in Australia and the United States: What are the differences in technology transfer, promotion, and acceptance?

Turtle excluder devices (TEDs) are being trialed on a voluntary basis in many Australian prawn (shrimp) trawl fisheries to reduce sea turtle captures. Analysis of TED introductions into shrimp trawl fisheries of the United States provided major insights into why conflicts occurred between shrimpers, conservationists, and government agencies. A conflict over the introduction and subsequent regulation of TEDs occurred because the problem and the solution were perceived differently by the various stakeholders. Attempts to negotiate and mediate the conflict broke down, resulting in litigation against the U.S. government by conservationists and shrimpers. Litigation was not an efficient resolution to the sea turtle-TED-trawl conflict but it appears that litigation was the only remaining path of resolution once the issue became polarized. We review two major Australian trawl fisheries to identify any significant differences in circumstances that may affect TED acceptance. Australian trawl fisheries are structured differently and good communication occurs between industry and researchers. TEDs are being introduced as mature technology. Furthermore, bycatch issues are of increasing concern to all stakeholders. These factors, combined with insights derived from previous conflicts concerning TEDs in the United Stares, increase the possibilities that TEDs will be introduced to Australian fishers with better acceptance.

Incubation of turtle eggs at different temperatures: Do embryos compensate for temperature during development?

Freshwater turtle eggs are normally subjected to fluctuations in incubation temperature during natural incubation. Because of this, developing embryos may make physiological adjustments to growth and metabolism in response to incubation at different temperatures. I tested this hypothesis by incubating eggs of the Brisbane river turtle Emydura signata under four different temperature regimes, constant temperatures of 24 degrees C and 31 degrees C throughout incubation, and two swapped-temperature treatments where incubation temperature was changed approximately halfway through incubation. Incubation at 31 degrees C took 42 d, and incubation at 24 degrees C look 78 d, with intermediate incubation periods for the swapped-temperature treatments. Hatchling mass, hatchling size, and total oxygen consumed during development were similar for all incubation regimes. The pattern of oxygen consumption during the last phase of incubation as reflected by rate of increase of oxygen consumption, peak oxygen consumption, and fall in oxygen consumption before hatching was determined solely by the incubation temperature during the last phase of incubation; that is, incubation temperature during the first phase of incubation had no influence on these factors. Thus there is no evidence of temperature compensation in growth or development during embryonic development of E. signata eggs.

Hapalotrema (Digenea : Spirorchidae) in the green turtle (Chelonia mydas) in Australia

Hapalotrema mehrai Rao, 1976 and Hapalotrema postorchis Rao, 1976 (Digenea: Spirorchidae) are redescribed from the heart and pulmonary arteries of the green turtle, Chelonia mydas, from Moreton Bay in south-eastern Queensland. Hapalotrema pambanensis Gupta and Mehrotra, 1981 from C. mydas in India is made a synonym of H. mehrai. Hapalotrema dorsopora Dailey, Fast and Balazs, 1993 from C. mydas from Hawaii was described with a dorsally opening uterine pore, but this is found to be the opening of Laurer's canal; therefore H. dorsopora is also made a synonym of H. mehrai. In addition to differences in the numbers of testes and general dimensions, H. mehrai and H. postorchis differ in the development of Laurer's canal and in the absence of a canalicular seminal receptacle in H. postorchis.

Effects of incubation temperature on the energetics of embryonic development and hatchling morphology in the Brisbane river turtle Emydura signata

Incubation temperature and the amount of water taken up by eggs from the substrate during incubation affects hatchling size and morphology in many oviparous reptiles. The Brisbane river turtle Emydura signata lays hard-shelled eggs and hatchling mass was unaffected by the amount of water gained or lost during incubation. Constant temperature incubation of eggs at 24 degrees C, 26 degrees C, 28 degrees C and 31 degrees C had no effect on hatchling mass, yolk-free hatchling mass, residual yolk mass, carapace length, carapace width, plastron length or plastron width. However, hatchlings incubated at 26 degrees C and 28 degrees C had wider heads than hatchlings incubated at 24 degrees C and 31 degrees C. Incubation period varied inversely with incubation temperature, while the rate of increase in oxygen consumption during the first part of incubation and the peak rate of oxygen consumption varied directly with incubation temperature. The total amount of oxygen consumed during development and hatchling production cost was significantly greater at 24 degrees C than at 26 degrees C, 28 degrees C and 31 degrees C. Hatchling mass and dimensions and total embryonic energy expenditure was directly proportional to initial egg mass.

Nest temperature and respiratory gases during natural incubation in the broad-shelled river turtle, Chelodina expansa (Testudinata : Chelidae)

Temperature was monitored in three natural nests, and oxygen and carbon dioxide partial pressure monitored in one natural nest of the broad-shelled river turtle, Chelodina expansa, throughout incubation. Nest temperature decreased after nest construction in autumn, remained low during winter and gradually increased in spring to a maximum in summer. In a nest where temperature was recorded every hour, temperature typically fluctuated through a 2 degrees C cycle on a daily basis throughout the entire incubation period, and the nest always heated faster than it cooled. Oxygen and carbon dioxide partial pressures in this nest were similar to soil oxygen and carbon dioxide partial pressures for the first 5 months of incubation, but nest respiratory gas tensions deviated from the surrounding soil over the last three months of incubation. Nest respiratory gas tensions were not greatly different from those in the atmosphere above the ground except after periods of rain. After heavy rain during the last 3 months of incubation the nest became moderately hypoxic (P-O2 similar to 100 Torr) and hypercapnic (P-CO2 similar to 50 Torr) for several successive days. These short periods of hypoxia and hypercapnia were not lethal.

Incubation of eggs of the Australian broad-shelled turtle, Chelodina expansa (Testudinata : Chelidae), at different temperatures: effects on pattern of oxygen consumption and hatchling morphology

Incubation temperature influences embryonic development and the morphology of resultant hatchlings in many species of turtle but few studies have addressed its effect on oxygen consumption and total embryonic energy expenditure. Eggs of the Australian broad-shelled river turtle, Chelodina expansa, were incubated at constant temperatures of 24 degrees C and 28 degrees C to determine the effect of temperature on oxygen consumption, embryonic energy expenditure and hatchling morphology. All embryos at both incubation temperatures experienced a period of developmental diapause immediately after oviposition. Once this initial diapause was broken, embryos underwent a further period of developmental arrest when the embryo was still very small and had minimal oxygen consumption (

Energy turnover in the normoxic and anoxic turtle heart

We examined the possibility that the heart of the turtle Chrysemys scripta is an exceptional anaerobic performer, by measuring myocardial power output, lactate output, and estimated ATP turnover in perfused heart preparations. Over a range of myocardial power outputs at 5 and 15 degrees C we find that turtle hearts perfused with anoxic saline do not show a particularly outstanding ability to produce ATP anaerobically. Furthermore, at 15 degrees C anoxia reduced the ATP turnover rate to 50% of the normoxic rate. At 5 degrees C the anoxia-induced depression of ATP turnover was even more pronounced, being 4-fold lower than the normoxic rate. In addition, anoxia at 5 degrees C reduced the basal metabolic rate of the turtle heart. We conclude that long-term cardiac tolerance of hypoxia in this species is more likely related to metabolic depression rather than to an exceptional anaerobic performance. (C) 1997 Elsevier Science Inc.

Does ecotourism contribute to sea turtle conservation? Is the flagship status of turtles advantageous?

There is little doubt that marine turtles are a flagship species for wildlife tourism. In some cases, this has turned out to be liability for sea turtle conservation, but in other cases, where for example turtle-based ecotourism has been developed, it has made a positive contribution to turtle conservation. Examples of both cases are given. Particular attention is given to the development of turtle-based ecotourism at Mon Repos Beach near Bundaberg, Australia. This development is set in its historical context and its contribution to conservation is discussed. Headstart projects for sea turtles in Sri Lanka are a tourist attraction. While they are promoted as having positive conservation consequences and a survey indicates that visitors are on the whole convinced of this, their effects on turtle conservation is uncertain. The farming of sea turtles provides a basis for tourism and can contribute to turtle conservation in ways outlined. It is argued that insufficient attention has been given to legends, culture and history associated with sea turtles in the promotion of turtle-based tourism. This is supported by Australian evidence. Insufficient use has been made of the connections of indigenous Australians with sea turtles in turtle-based tourism. Beneficial scope exist for developing connections between man and turtles further than at present in promoting turtle-based tourism. This could add further to the role of turtle-based tourism in promoting turtle conservation.

Public valuation of and attitudes towards the conservation and use of the Hawksbill turtle: An Australian case study

Managing hawksbill turtle populations for use and conservation requires (i) adequate scientific understanding of their population status and dynamics and (ii) consideration of the public’s attitudes to this species. This study employs experimental surveys to assess the Australian public’s attitudes towards the hawksbill turtle, their knowledge of it, their views about its sustainable commercial harvesting, and their support and financial contribution for the species’ conservation. Contingent valuation reveals that the Australian public’s willingness to contribute to the conservation of the hawksbill turtle is high even in comparison to threatened Australian bird and mammal fauna. Most of this stated contribution is based on the intrinsic (non-use) value associated with the hawksbill turtle. It seems that the Australian public will only accept its harvesting if the sustainability of this is assured and its population is more secure. The CITES categorisation of the hawksbill as an Appendix I species hampers the development of techniques for its sustainable use.

Development of the pulmonary surfactant system in the green sea turtle, Chelonia mydas

This study describes the developmental changes in pulmonary surfactant (PS) lipids throughout incubation in the sea turtle, Chelonia mydas. Total phospholipid (PL), disaturated phospholipid (DSP) and cholesterol (Chol) harvested from lung washings increased with advancing incubation, where secretion was maximal at pipping, coincident with the onset of pulmonary ventilation. The DSP/PL ratio increased, whereas the Chol/PL and the Chol/DSP ratio declined throughout development. The phospholipids, therefore, are independently regulated from Chol and their development matches that of mammals. To explore whether hypoxia could elicit an effect on the development of the PS system, embryos were exposed to a chronic dose of 17% O-2 for the final similar to 40% of incubation. Hypoxia did not affect incubation time, absolute, nor relative abundance of the surfactant lipids, demonstrating that the development of the system is robust and that embryonic development continues unabated under mild hypoxia. Hypoxia-incubated hatchlings had lighter wet lung weights than those from normoxia, inferring that mild hypoxia facilitates lung clearance in this species. (C) 2001 Elsevier Science B.V. All rights reserved.

Temperature variation within and between nests of the green sea turtle, Chelonia mydas (Chelonia : Cheloniidae) on Heron Island, Great Barrier Reef

Four temperature data-loggers were placed in each of five green sea turtle nests on Heron Island in the 1998-99 nesting season. Temperatures in all nests increased as incubation progressed due to general sand heating and increased metabolic heat production of the developing embryos. Even at the top of nests no daily diurnal fluctuation in temperature was evident. The temperature of eggs in the middle of the nest increased above those in the nest periphery during the last third of incubation. However, this metabolic nest heating would have little effect on hatchling sex ratio because it occurred after the sex-determining period. Small differences in temperature between regions of a nest persisted throughout incubation and may be important in ensuring the production of at least some individuals of the opposite sex in nests that have temperatures close to either the all-male or all-female determining temperatures. Location and degree of shading of nests had little effect on mean nest temperature, but deeper nests were generally cooler and therefore were predicted to produce a higher proportion of males than were shallower nests. Nest temperature profile data indicated that the 1998-99 nesting season on Heron Island would have produced a strongly female-biased sex ratio amongst hatchlings.

Incubation temperature, energy expenditure and hatchling size in the green turtle (Chelonia mydas), a species with temperature-sensitive sex determination

Eggs from the Heron Island, Great Barrier Reef, nesting population of green turtles (Chelonia mydas) were incubated at all-male-determining (26 degreesC) and all-female-determining (30 degreesC) temperatures. Oxygen consumption and embryonic growth were monitored throughout incubation, and hatchling masses and body dimensions were measured from both temperatures. Eggs hatched after 79 and 53 days incubation at 26 degreesC and 30 degreesC respectively. Oxygen consumption at both temperatures increased to a peak several days before hatching, a pattern typical of turtle embryos, and the rate of oxygen was higher at 30 degreesC than 26 degreesC. The total amount of energy consumed during incubation, and hatchling dimensions, were similar at both temperatures, but hatchlings from 26 degreesC had larger mass, larger yolk-free mass and smaller residual yolks than hatchlings from 30 degreesC. Because of the difference in mass of hatchlings, hatchlings from 30 degreesC had a higher production cost.