The Benefits of Nest Relocation Extend Far Beyond Recruitment: A Rejoinder to Mrosovsky

Individual sea turtle nests have an extremely low probability of producting adult turtles; thus the practice of moving nests away from the ocean (where they will not be inundated by seawater) is a questionable conservation strategy. Recently in Environmental Management, Mrosovosky used the repeatability of nesting female turtles to place their eggs in certain locations to infer that some females may consistently nest in areas which will be flooded, lowering the chance that any eggs will hatch. This information was used to hypothesize that saving “doomed” sea turtle nests may then alter the genetic composition of the population, ultimately resulting in turtles that nest in poor habitats. Here I question Mrosovosky’s argument by focusing on several weaknesses inherent in the original article, namely that at present there is no evidence to suggest that nest-site selection is a heritable trait with an underlying genetic basis.     

Against Oversimplifying the Issues on Relocating Turtle Eggs

Translocating sea turtle eggs at risk from high tides to safer places is one of the most widely undertaken conservation measures on behalf of these species. Recent research work has shown that individual female turtles differ in their nest-site preferences. If more of the nests saved by translocation come from turtles with tendencies to lay near the water, might this perhaps interfere with natural selection? This possibility adds to the controversy already surrounding relocation of turtle nests.     

Stream and riparian management for freshwater turtles

The regulation and management of stream ecosystems worldwide have led to irreversible loss of wildlife species. Due to recent scrutiny of water policy and dam feasibility, there is an urgent need for fundamental research on the biotic integrity of streams and riparian zones. Although riverine turtles rely on stream and riparian zones to complete their life cycle, are vital producers and consumers, and are declining worldwide, they have received relatively little attention. I review the literature on the impacts of contemporary stream management on freshwater turtles. Specifically, I summarize and discuss 10 distinct practices that produce five potential biological repercussions. I then focus on the often-overlooked use of riparian zones by freshwater turtles, calculate a biologically determined riparian width, and offer recommendations for ecosystem management. Migration data were summarized on 10 species from eight US states and four countries. A riparian zone encompassing the majority of freshwater turtle migrations would need to span 150 m from the stream edge. Freshwater turtles primarily chose high, open sandy habitats to nest. Nests in North America contained eggs and hatchlings during April through September and often through the winter. In addition, freshwater turtles utilized diverse riparian habitats for feeding, nesting, and overwintering. Additional documentation of stream and riparian habitat use by turtles is needed.     

Do Embedded Roadway Lights Protect Sea Turtles?

Street lighting on coastal roadways is often visible at sea turtle nesting beaches, and disrupts the nocturnal orientation of hatchlings as they crawl toward the sea. Our objective was to determine whether an alternative lighting system (light-emitting diodes, embedded in the roadway pavement) prevented orientation disruption. Hatchlings at the beach oriented normally when only the embedded lights were on, or when all lighting was switched off. However, turtles showed poor orientation when street lighting was on. Measurements confirmed that street lighting was scattered to the beach, whereas embedded lighting was not. We conclude that embedded lighting keeps the beach dark and thus protects sea turtles. However, on two overcast evenings, lighting (“skyglow”) from nearby development, reflected by cloud cover to the beach, weakened hatchling orientation. Thus, both indirect (reflected) and direct sources of lighting negatively impact the turtles.     

Do Open-Cycle Hatcheries Relying on Tourism Conserve Sea Turtles? Sri Lankan Developments and Economic–Ecological Considerations

By combining economic analysis of markets with ecological parameters, this article considers the role that tourism-based sea turtle hatcheries (of an open-cycle type) can play in conserving populations of sea turtles. Background is provided on the nature and development of such hatcheries in Sri Lanka. The modeling facilitates the assessment of the impacts of turtle hatcheries on the conservation of sea turtles and enables the economic and ecological consequences of tourism, based on such hatcheries, to be better appreciated. The results demonstrate that sea turtle hatcheries serving tourists can make a positive contribution to sea turtle conservation, but that their conservation effectiveness depends on the way they are managed. Possible negative effects are also identified. Economic market models are combined with turtle population survival relationships to predict the conservation impact of turtle hatcheries and their consequence for the total economic value obtained from sea turtle populations.     

Modeling protected species as an undesirable output: the case of sea turtle interactions in Hawaii's longline fishery

Interactions with sea turtles have occurred at an alarming rate in swordfish longlining in Hawaii in recent years and various regulations have been put forward to protect sea turtles. In order to understand the cost of reducing sea turtle interactions, methods have been developed to derive the shadow price of sea turtle bycatch based on fisher's welfare loss from a specific regulation. This paper illustrates an alternative method of calculating temporal and trip-specific cost of sea turtle bycatch reduction. The advantages of this method lie in the computation of shadow price without assuming specific regulation implementation and its relatively modest data requirement. A parametric output distance function is used to simultaneously model desirable and undesirable catches. Using the duality argument, the revenue-related shadow price of sea turtle bycatch can be derived from the estimated distance function. Average shadow price of sea turtle bycatch for the period 1991-1999 is estimated to be US $30873 in 1991 dollars. Average shadow prices of sea turtle bycatch by trip characteristics, such as fishing year, trip type and location are also estimated. Such information can be useful for policy makers to analyze tradeoffs and make appropriate policy decisions.     

Accidental Bait: Do Deceased Fish Increase Freshwater Turtle Bycatch in Commercial Fyke Nets?

Bycatch of turtles in passive inland fyke net fisheries has been poorly studied, yet bycatch is an important conservation issue given the decline in many freshwater turtle populations. Delayed maturity and low natural adult mortality make turtles particularly susceptible to population declines when faced with additional anthropogenic adult mortality such as bycatch. When turtles are captured in fyke nets, the prolonged submergence can lead to stress and subsequent drowning. Fish die within infrequently checked passive fishing nets and dead fish are a potential food source for many freshwater turtles. Dead fish could thus act as attractants and increase turtle captures in fishing nets. We investigated the attraction of turtles to decomposing fish within fyke nets in eastern Ontario. We set fyke nets with either 1 kg of one-day or five-day decomposed fish, or no decomposed fish in the cod-end of the net. Decomposing fish did not alter the capture rate of turtles or fish, nor did it alter the species composition of the catch. Thus, reducing fish mortality in nets using shorter soak times is unlikely to alter turtle bycatch rates since turtles were not attracted by the dead fish. Interestingly, turtle bycatch rates increased as water temperatures did. Water temperature also influences turtle mortality by affecting the duration turtles can remain submerged. We thus suggest that submerged nets to either not be set or have reduced soak times in warm water conditions (e.g., >20 °C) as turtles tend to be captured more frequently and cannot withstand prolonged submergence.     

Connecting international priorities with human wellbeing in low-income regions: lessons from hawksbill turtle conservation in El Salvador

Hawksbill turtles (Eretmochelys imbricata) are highly endangered in the eastern Pacific Ocean, yet their eggs continue to be an important subsistence resource for impoverished coastal residents in El Salvador. In this study, we use naturalistic inquiry to explain the realities experienced by coastal residents who share habitat with hawksbills in El Salvador, and then suggest implications of the disparities between these realities and international priorities for hawksbill conservation and community development in El Salvador and other low-income regions. To provide a context for understanding hawksbill conservation and its implications for similar challenges related to conservation and wellbeing, we first summarise the conservation context, including the emergence of sea turtle conservation in El Salvador. We then describe our naturalistic approach, including the ethnographic methodology for this study. Finally, we detail the analysis of interviews conducted with tortugueros (i.e. local sea turtle egg collectors), to help explain how hawksbills fit into local realities. Our results demonstrate that, from the perspective of tortugueros, (1) the primary importance of hawksbills is the economic value attached to egg sales, but there exists a deeper connection to local culture; (2) egg purchase by hatcheries is a socially just conservation strategy that benefits both hawksbill and human wellbeing; and (3) opportunities for local residents to participate in decision-making regarding sea turtle conservation are limited, and should be increased. We argue that harmonising international conservation priorities with local community development realities is one path towards simultaneously contributing to long-term sea turtle recovery and human wellbeing in low-income regions.     

Welfare and Environmental Implications of Farmed Sea Turtles

Various captivity-related health problems have been described as arising in the farming of sea turtles at the Cayman Turtle Farm (CTF). Our study included a desktop review of turtle farming, direct onsite inspection at the CTF, assessment of visual materials and reports provided by investigators from the World Society for the Protection of Animals (WSPA), and a limited analysis of water quality for potential pathogens. In particular, we assessed physical and behavioural condition of animals for signs of stress, injury and disease. During the onsite inspection we identified three distinct signs of physical injury and disease, six distinct signs of abnormal and problematic arousal- and discomfort-related behaviour; and three distinct signs of normal quiescence- and comfort-related behaviour. On evaluation of evidence provided by the WSPA we identified ten distinct signs of physical injury and disease, and management- or genetic-related conditions; six distinct signs of abnormal and problematic arousal- and discomfort-related behaviour; and three distinct signs of normal quiescence- and comfort-related behaviour. We conclude that sea turtles at the CTF manifested important physical and behavioural signs that are indicative of problematic management and captivity-related stress, and the limitations of sea turtle adaptive plasticity in captivity. The problematic physical and behavioural signs, in our view, related to the inherent nature of intensive turtle propagation which in particular involves overt- and crypto-overcrowding and understimulating environments, and an associated failure to meet all the physical, biological and innate behavioural needs of sea turtles.     

Using expert opinion to prioritize impacts of climate change on sea turtles’ nesting grounds

Managers and conservationists often need to prioritize which impacts from climate change to deal with from a long list of threats. However, data which allows comparison of the relative impact from climatic threats for decision-making is often unavailable. This is the case for the management of sea turtles in the face of climate change. The terrestrial life stages of sea turtles can be negatively impacted by various climatic processes, such as sea level rise, altered cyclonic activity, and increased sand temperatures. However, no study has systematically investigated the relative impact of each of these climatic processes, making it challenging for managers to prioritize their decisions and resources. To address this we offer a systematic method for eliciting expert knowledge to estimate the relative impact of climatic processes on sea turtles’ terrestrial reproductive phase. For this we used as an example the world’s largest population of green sea turtles and asked 22 scientists and managers to answer a paper based survey with a series of pair-wise comparison matrices that compared the anticipated impacts from each climatic process. Both scientists and managers agreed that increased sand temperature will likely cause the most threat to the reproductive output of the nGBR green turtle population followed by sea level rise, then altered cyclonic activity. The methodology used proved useful to determine the relative impact of the selected climatic processes on sea turtles’ reproductive output and provided valuable information for decision-making. Thus, the methodological approach can potentially be applied to other species and ecosystems of management concern.     

Nest-Site Selection by Black Sparrowhawks Accipiter melanoleucus: Implications for Managing Exotic Pulpwood and Sawlog Forests in South Africa

This study provides timber growers with silvicultural guidelines for establishing and maintaining nest-tree habitat for native black sparrowhawks (Accipiter melanoleucus) in commercial planted forests in South Africa. In this country, exotic eucalypts and pines are planted principally for pulpwood and sawlog production. Nineteen nests were sampled in indigenous forests and 58 nests in exotic forests. Although mean nest heights differed between indigenous and exotic trees, in all trees, nests were positioned, on average, at 64% of tree height. Black sparrowhawks nested near stand edges, probably seeking a compromise between nesting adjacent to open hunting habitat and selecting an insulated tree from within the forest. Black sparrowhawks nested in tall trees ( X- = 18-33 m for different tree species classes) with a large diameter (>60 cm). Unfortunately, the South African pulpwood and sawlog industry employ short rotations (<16 years) and high tree densities (>700 trees/ha) that do not allow the trees to attain the characteristics suitable for black sparrowhawk nesting sites. Eucalypt and pine nest stands must be of 25 x 25 m minimum size and incorporate 10 trees at minimum heights of 21 and 18 m and diameters of 37 and 35 cm, respectively. If such nest-tree stands are set aside as islands in a sea of commercial forests, and black sparrowhawks and other forest raptors nest in them, timber growers will improve the tree-nesting raptor diversity of planted forests. If, however, these raptors prey upon species of conservation importance, the management recommendations could be reversed to limit the potential for predation.     

Effects of Military Training Activities on Shrub-steppe Raptors in Southwestern Idaho, USA

Buteo regalis ), northern harriers (Circus cyaneus), burrowing owls (Athene cunicularia), and short-eared owls (Asio flammeus) inside and outside a military training site in the Snake River Birds of Prey National Conservation Area, southwestern Idaho. The Orchard Training Area is used primarily for armored vehicle training and artillery firing by the Idaho Army National Guard. Relative abundance of nesting pairs inside and outside the training site was not significantly different from 1991 to 1993 but was significantly higher on the training site in 1994 (P ≤ 0.03). Nesting success varied among years but was not significantly different inside and outside the training site (P > 0.26). In 1994, short-eared owl and burrowing owl nests were significantly closer to firing ranges used early in the spring before owls laid eggs than were random points (P < 0.001). In 1993, distances from occupied burrowing owl nests to firing ranges used early in the year were similar to those from random points to the same firing ranges (P = 0.16). Military activity contributed to some nesting failures from 1992 to 1994, but some pairs nested successfully near military activity.     

MPA in Labor: Securing the Pearl Cays of Nicaragua

Implementation of Marine Protected Areas (MPAs) has always a step-zero, i.e., an initial phase when the idea is incepted, communicated and negotiated among stakeholders. What happens during this phase is likely to have an impact later on. If not done right, the management of the MPA may encounter problems at later stage that will be difficult to correct. Inspired by this working theory, this article describes the effort to establish the Pearl Cays off the Caribbean coast of Nicaragua as a protected area. This case-study illustrates the critical actions to be taken during step-zero, i.e., what needs to be considered and done before an MPA is formally declared. The area investigated consists of a number of small islands (cays) and coral reefs, fishing grounds and marine turtle nesting areas. Throughout history, the cays have played an important role in sustaining livelihoods of nearby communities. Although the idea of an MPA was originally conservation, the communities saw it as an opportunity to regain ownership and control of the cays. By Nicaraguan law, in order to establish protected areas, consultation and approval from local people is required. In the case of the Pearl Cays, this has proved difficult. The article demonstrates how MPA initiatives must sometimes relate to already ongoing complex social processes in the area where they are to be instigated.     

Unexpected threat from conservation to endangered species: reflections from the front-line staff on sea turtle conservation

This study described the paradox created by the efforts of a conservation organization, which caused an emerging threat to the survival of an endangered species, as well as proposed recommendations to mitigate this paradox. In-depth interviews were conducted to investigate the problems encountered during the implementation of conservation practices by green sea turtle conservation workers (volunteers) in Lanyu, Taiwan. The staff believed that the implementation of the green sea turtle conservation measures violated the traditional cultural beliefs of the local residents (Tao/Yami ethnic group), which caused resentment by the residents towards the organization. Consequently, the residents did not cooperate with the organization and even discouraged conservation activities. In addition, green sea turtle ecotourism promoted by the conservation organization in recent years violated local customs of not having contact with green sea turtles or entering their habitats.     

Conservation and management of the American crocodile

The American crocodile is a rare and endangered species, the range of which has contracted to disjunct locations such as Hispaniola, Jamaica, Cuba, Panama, and southern Florida. In an attempt to determine what factors might be limiting population growth, an extensive collaborative research program was conducted in 1978–82 in southern Florida. Limiting factors explicitly studied included climate, hurricanes, population dispersion, nesting habitat, fertility, predation, nest chamber environment, juvenile survivorship, artificial mortality, disturbance, and environmental contamination. No single natural factor limits the population, although in concert various factors result in low adult recruitment rates. Such natural limitations explain the natural rarity of this tropical species at the temperate limits of its range. Two artificial sources of mortality are death of adults on roads and the flooding of nests by high groundwater tables. These sources of mortality are potentially controllable by the appropriate management agencies. Active management, by such means as protection of individuals, habitat preservation and enhancement, nest site protection, and captive breeding, is also appropriate for assuring the survival of a rare species. The American crocodile has survived in southern Florida in face of extensive human occupancy of parts of its former nesting habitat, demonstrating the resilience of a threatened species. This case history illustrates the efficacy of conducting research aimed at testing specific management hypotheses, the importance of considering biographical constraints limiting population status in peripheral populations, the need for active management of rare species, and the role of multiple reserves in a conservation and management strategy.     

Potential Applicability of Persuasive Communication to Light-Glow Reduction Efforts: A Case Study of Marine Turtle Conservation

Artificial lighting along coastlines poses a significant threat to marine turtles due to the importance of light for their natural orientation at the nesting beach. Effective lighting management requires widespread support and participation, yet engaging the public with light reduction initiatives is difficult because benefits associated with artificial lighting are deeply entrenched within modern society. We present a case study from Queensland, Australia, where an active light-glow reduction campaign has been in place since 2008 to protect nesting turtles. Semi-structured questionnaires explored community beliefs about reducing light and evaluated the potential for using persuasive communication techniques based on the theory of planned behavior (TPB) to increase engagement with light reduction. Respondents (n = 352) had moderate to strong intentions to reduce light. TPB variables explained a significant proportion of variance in intention (multiple regression: R ² = 0.54–0.69, P < 0.001), but adding a personal norm variable improved the model (R ² = 0.73–0.79, P < 0.001). Significant differences in belief strength between campaign compliers and non-compliers suggest that targeting the beliefs reducing light leads to “increased protection of local turtles” (P < 0.01) and/or “benefits to the local economy” (P < 0.05), in combination with an appeal to personal norms, would produce the strongest persuasion potential for future communications. Selective legislation and commitment strategies may be further useful strategies to increase community light reduction. As artificial light continues to gain attention as a pollutant, our methods and findings will be of interest to anyone needing to manage public artificial lighting.     

Double-Crested Cormorant (Phalacrocorax auritus) Nesting Effects on Understory Composition and Diversity on Island Ecosystems in Lake Erie

The context for this study is the management concerns over the severity and extent of the impact of cormorants on island flora in the recent past on Lake Erie islands. Accordingly, this study sought to quantify the nesting colonies' influence on coarse woody litter and how nest densities and litter depth may influence the herbaceous layer, the seed bank composition and viability across the extent of three Lake Erie islands. The data for this study were collected from 2004 to 2008 on East Sister Island and Middle Island using two main strategies. First, herbaceous layer surveys, cormorant nest counts, soil seed bank cores, and litter depth measurements were executed using a plotless-point quarter method to test island-wide impacts from nesting activities (data were also collected on a third island, West Sister Island as a reference for the other two islands). Secondly, a sub-sample of the entire plot set was examined in particularly high nesting density areas for two islands (Middle Island and East Sister Island). Kruskal-Wallis tests indicated that there are subtle changes in the herbaceous diversity (total, native and exotic) and seed bank composition across the islands. The sub sample set of the plots demonstrated that Phalacrocorax auritus nest density does influence litter depth, herbaceous species abundance and diversity. Cormorant nesting pressures are restricted to areas of high nesting pressures and competition. However, there remains a risk to the interior herbaceous layer of the island if the effects of nesting pressures at the edges advance inward from this perimeter.     

Reestablishing Naturally Functioning Dunes on Developed Coasts

Common beach management practices reduce the ecological values of coastal dunes. Mechanical beach cleaning eliminates incipient dunes, habitat for nesting birds, seed sources for pioneer dune colonizers and food for fauna, and artificially small, stabilized foredunes reduce the variability in microenvironments necessary for biodiversity. Recent initiatives for reducing coastal hazards, protecting nesting birds, and encouraging nature-based tourism provide incentive for the development of a restoration program for beaches and dunes that is compatible with human use. Suggested changes in management practice include restricting or rerouting pedestrian traffic, altering beach-cleaning procedures, using symbolic fences to allow for aeolian transport while preventing trampling of dunes, and eliminating or severely restricting exotic species. Landforms will be more natural in function and appearance but will be more dynamic, smaller and in a different position from those in natural areas. Research needs are specified for ecological, geomorphological, and attitudinal studies to support and inform restoration planning.     

What Makes Them Pay? Values of Volunteer Tourists Working for Sea Turtle Conservation

As charismatic mega-fauna, sea turtles attract many volunteers to conservation programs. This article examines the ways in which volunteers value sea turtles, in the specific context of volunteers working with the Caribbean Conservation Corporation, at Tortuguero, Costa Rica. The complexity of volunteer values is explored using a qualitative approach. In-depth interviews with 31 volunteers were conducted in July of 1999 and 2000. Interviews probed, among other things, interest in sea turtles and their conservation, motives for participating, and the most gratifying parts of their volunteer experience. Results show that volunteers hold multiple and complex values for sea turtles, but particular values dominate. Results have implications for understanding human–environment relations and the emerging study of volunteer tourism. There are also management implications for volunteer programs hoping to attract participants.