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DOAJ Open Access 2025
Approaches to legal governance in constructing Nanhai National Marine Park

Yuwen Huang, Minyou Yu

As a globally significant marine ecosystem, the South China Sea faces multiple challenges including overfishing, ecological degradation, and geopolitical conflicts. To balance ecological conservation with resource development needs, establishing a South China Sea National Marine Park has emerged as a critical strategy. This paper employs literature analysis, comparative research, and policy evaluation methods to investigate legal governance frameworks for the marine park. The study reveals that China’s current marine conservation legal framework faces challenges such as fragmented legislation, weak enforcement mechanisms, and inadequate integration between international and domestic laws, which hinder cross-border ecological cooperation. To address these issues, the paper proposes enhancing specialized domestic legislation, optimizing enforcement and supervision systems, and promoting regional marine conservation agreements to establish a legal framework tailored to the South China Sea’s unique characteristics. The research also demonstrates that legal development for the marine park must reconcile ecological integrity with geopolitical realities, fostering regional cooperation and trust through legal innovation. This study offers a feasible legal pathway for ecological governance in disputed waters while laying the foundation for sustainable blue economy development.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2025
Decoding growth parameters of small pelagics: a critical examination of model effectiveness with a focus on the European anchovy

Margarita Rincón Hidalgo, Margarita Rincón Hidalgo, MariAngeles Gamaza et al.

Traditionally, parameters defining life history traits, such as growth, were solely determined through length or age–length databases and then included as fixed in integrated stock assessment models. In current practice, growth parameters are usually estimated within these models (“inside”) and fitted to other datasets. However, for short-lived and small pelagic species, challenges may arise, particularly when there is a high variability in the age–length data or sampling biases are inadequately identified or addressed by these models. To test model effectiveness in capturing the growth dynamics of these species, we propose a comparative analysis following recommended practices for incorporating age–length data into integrated stock assessment models for the specific case of anchovy (Engraulis encrasicolus) stock in the Gulf of Cadiz. The reason is twofold: its significant ecological and economic importance and the need to improve the accuracy of growth parameter estimates used to inform total allowable catch (TAC) scientific advice. The overarching goal of this analysis is to identify the optimal model configuration that provides accurate growth parameter estimates. Our approach shows that random effects can effectively estimate growth in species with high age–length variability. Furthermore, using the obtained estimates as fixed in the stock assessment model reduces computational time and enhances the goodness of fit, resulting in a more efficient model. The results address a significant gap in existing integrated models used for scientific advice, which often do not have the “random effects on parameters” feature. Notably, this framework is widely applicable to other short-lived small pelagic species that typically exhibit a high data variability, offering a valuable solution for improving efficiency and robustness in fisheries management decision-making.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2025
Insights on avian life history and physiological traits in Central Africa: ant-following species have young-dominated age ratios in secondary forest

Panagiotis Nikolaou, Panagiotis Nikolaou, Panagiotis Nikolaou et al.

The Congo Basin rainforest and adjacent Lower Guinea Forest constitute the second largest tract of lowland tropical rainforest in the world. As with the rest of the continent, human population is increasing rapidly and forest degradation is ubiquitous. Forest degradation through logging has pervasive negative effects on ecosystems, but selective logging is considered less impactful than clearcutting. Recent research in Afrotropical forest shows that certain avian species and guilds are more affected by selective logging than others (e.g., specialist insectivores such as followers of Dorylus driver ants); however, the mechanisms behind these patterns are poorly known. In an eight-year mist-netting effort in Equatorial Guinea, we caught 1193 birds in primary forest and high-grade selectively logged forest to determine the effect of disturbance on six demographic and physiological measures on birds. We compared five life history and population traits for ten insectivorous species: proportion of breeding and molting birds, molt-breeding overlap, bird age, and a body mass index. We also analyzed the concentrations of the stress hormone feather corticosterone (fCORT) in five species. All three strict ant-following species (Alethe castanea, Chamaetylas poliocephala, Neocossyphus poensis), and the Muscicapid robin Sheppardia cyornithopsis had a higher proportion of first year birds in secondary forest. Furthermore, two ant-followers, A. castanea and C. poliocephala, had a higher proportion of individuals molting in primary forest. Finally, only Illadopsis cleaveri had higher body condition in secondary forest. We found no differences in breeding status, molt-breeding overlap or fCORT between forest types. Using a long-term mist-netting effort, we use measures taken from birds in-the-hand to go beyond insights from point counts alone; we gain valuable insights into the demography and physiology of Afrotropical birds occupying variably degraded lowland tropical rainforest.

General. Including nature conservation, geographical distribution
DOAJ Open Access 2024
Cultural keystone species and their role in biocultural conservation

Jessica Lukawiecki, Faisal Moola, Robin Roth

Abstract Biocultural diversity is declining globally. Cultural keystone species (CKS) are one promising pathway by which biocultural approaches to conservation, which seek to protect both biological and cultural diversity, might be implemented in practice. We traced the evolution of the CKS concept in relation to Indigenous Peoples in the Canadian context through a scoping review of the literature from 2000 to 2021 and nine in‐depth interviews with Indigenous Guardians and knowledge holders. Emergent themes in this scoping review indicate that CKS, rather than being viewed as objects for conservation, can be understood as ongoing relationship(s) between the cultural and ecological, which are intimately tied to language, knowledge, practices, and places in ways that are deeply interconnected. One cannot protect CKS, therefore, without also protecting the relationships that people (or groups of people) have to that species. We conclude by recommending further investment in policies and programs that support enabling mechanisms for Indigenous Peoples to maintain, manage, and restore relationships with CKS.

Ecology, General. Including nature conservation, geographical distribution
DOAJ Open Access 2024
Inclusion effect of jack mackerel meal in olive flounder (Paralichthys olivaceus) diet substituting blended fish meal with tuna by-product meal on growth, feed availability, and economic efficiency

Md. Rabiul Islam, Md. Rabiul Islam, Sung Hwoan Cho et al.

The low fish meal (FM) diet commonly causes deteriorated palatability, and eventually leads to lowered feed consumption and growth performance of fish. This study was, therefore, designed to determine inclusion impact of the graded levels of jack mackerel meal (JMM) in olive flounder (P. olivaceus) diets replacing 50% FM with tuna by-product meal (TBM) on growth, feed availability, biochemical composition, blood chemistry, and economic efficiency. Six isonitrogenous (55.5%) and isolipidic (10.0%) diets were formulated. Sixty percent FM was incorporated in the control (Con) diet. In the Con diet, fifty percent of FM was replaced by TBM, and then 10, 20, 30, 40, and 50% JMM were included at the cost of FM, referred as the TJ10, TJ20, TJ30, TJ40, and TJ50 diets, respectively. Three hundred and sixty juvenile fish (18.0 ± 0.01g; mean ± SD) were delivered into 18, 50-L flow-through tanks. All diets were randomly assigned to triplicate groups of fish. Fish were hand-fed to apparent satiation twice daily for 56 days. Weight gain, specific growth rate, and feed consumption of fish fed the TJ30, TJ40, and TJ50 diets were significantly (P < 0.001, P < 0.001, and P < 0.002, respectively) greater than those of fish fed the Con and TJ10 diets, but not significantly (P > 0.05) different from those of fish fed the TJ20 diet. Feed utilization, proximate composition, amino acid profiles, and blood chemistry of fish were not significantly (P > 0.05) altered by dietary treatments. However, the TJ30 diet was the most recommendable to farmers in terms of economic profit index (EPI). Conclusively, 30% inclusion of JMM is the most recommendable in the olive flounder diet substituting 50% FM with TBM based on growth performance, feed availability, and EPI.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2023
Setting the basis for transient DNA transformation and transformant selection in the red macroalga Gracilariopsis lemaneiformis

Morgane Eléouët, Morgane Eléouët, Ni Zhang et al.

Gracilariopsis lemaneiformis (Gp. lemaneiformis) is an economically important agar-producing red alga applicable in the food and cosmetic industries. The genetic knowledge of this species is, however, limited, and genetic tools for studying and engineering it are lacking. This has limited the understanding of its developmental genetics and hindered the development of new strains, and developing genetic tools would allow to tackle these problems. Here, transient DNA transformation via microparticle bombardment is reported for the first time in this species, as well as efficient exogenous gene expression driven by the CaMV35S promoter, the endogenous GlAct1 promoter, and the Pyropia yezoensis PyAct1 promoter in the transformed branches. Moreover, the Blue Fluorescent Protein (BFP) is demonstrated to be a suitable reporter gene for studies in Gp. lemaneiformis. Screening of antibiotic sensitivity is needed for the development of transient DNA transformation, and selection of transformants is also reported in the alga. Hygromycin B (Hyg) is determined to be the most effective antibiotic for Gp. lemaneiformis selection. The Hyg resistance gene driven by the CaMV35S promoter is shown to confer resistance to Hyg at a concentration of 1 mg.ml-1, but no transformed individual could be regenerated so far. These results are promising for future refining of the experimental conditions, for instance, by using different promoters and developing techniques for facilitating the penetration of the DNA in the cells.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2023
Drivers of human–black caiman (Melanosuchus niger) conflict in Indigenous communities in the North Rupununi wetlands, southwestern Guyana

Meshach A. Pierre, Kim S. Jacobsen, Matthew T. Hallett et al.

Abstract Recovering populations of large carnivores impact the people that live alongside them, sometimes leading to conflict and lethal retaliation. One such carnivore, the black caiman (Melanosuchus niger) has been implicated in the destruction of fishing equipment, depredation of livestock and pets, and attacks on humans. In order to understand how various stakeholder groups are affected by the negative impacts of living alongside caiman, and their resulting attitudes and behaviors towards caiman, we conducted semistructured interviews in seven Indigenous communities in southwestern Guyana from November 2017 to October 2019. We used logistic and ordinal regression to identify demographic indicators of fishing behavior and factors that are associated with negative attitudes and antagonistic behavior. Loss of pets in addition to an effect of gender, rather than competition overfishing resources (as hypothesized) may drive conflict between Indigenous communities and black caiman. We propose site differences, such as ecotourism may affect attitudes about and behavior towards caiman. The presence of impacts on communities and retaliatory behavior indicates that human–wildlife and wildlife–human impacts involving black caiman may be a concern for the recovery of the species' populations, and the communities that coexist with them.

Ecology, General. Including nature conservation, geographical distribution
DOAJ Open Access 2022
Pando's pulse: Vital signs signal need for course correction at world‐renowned aspen forest

Paul C. Rogers

Abstract Upland aspen (Populus spp.) forests contribute significantly to biodiversity in their circumboreal role as keystone species. As aspen ecosystems flourish or diminish, myriad dependent species follow suit. The 43‐hectare Pando aspen (Populus tremuloides Michx.) clone in Utah, USA, is thought to be the largest living organism on earth, but is faltering due to chronic herbivory. Long‐term resilience in aspen communities, including Pando, rests on successful recruitment of vegetative suckers that are nutritiously desirable to browsing ungulates. Here, I evaluate aspen reproduction alongside numerous vital indicators of Pando's status in the first trend assessment of this embattled iconic forest. I remeasured 64 plots from 2017 using 19 indicators to determine current conditions. Findings show that the genetically uniform Pando is “breaking up” because of herbivory and fencing. Initial successes within fenced zones are tempered by nearly half of Pando that remains unprotected from chronic wild and domestic herbivory. I propose a strategy of process‐based stewardship informed by adaptive monitoring to restore this famed “one‐tree forest.” Lessons from Pando may be applied to struggling, often species rich, aspen systems facing similar challenges globally.

Ecology, General. Including nature conservation, geographical distribution
DOAJ Open Access 2022
Forced vs. Intrinsic Wintertime Submonthly Variability of Sea Surface Temperature in the Midlatitude Western North Pacific

Yusheng Wu, Guidi Zhou, Guifen Wang et al.

The relative importance of wintertime forced and intrinsic SST variability in the Kuroshio-Oyashio Extension (KOE) region on submonthly timescales (2–10 and 10–30 days) is evaluated based on theoretical, observational, and modeling analysis. It is shown that the theoretical framework extended from the stochastic climate model has difficulties in representing observed SST variability on such short scales. We then employ the single-column General Ocean Turbulence Model (GOTM) to explicitly evaluate the SST variability forced by atmospheric disturbances. Results show that in the KOE region forced SST variability is responsible for a very small fraction of the total variability (<10%) on the submonthly scales, indicating the dominance of intrinsic oceanic processes. Outside the KOE forced variability dominates. By means of sensitivity experiments, the key physical factors are identified: upper ocean vertical mixing, wind stress forcing (mainly for outside KOE), and latent heat flux, the former two of which are not considered in the theoretical framework. The above results are robust against different levels of submonthly SST variability.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2021
Modulation of Antioxidant Enzymes, Heat Shock Protein, and Intestinal Microbiota of Large Yellow Croaker (Larimichthys crocea) Under Acute Cold Stress

Huirong Lv, Yanli Liu, Haidong Li et al.

The experiment was conducted in a sealed, temperature-controlled room. The initial water temperature of the treatment group was 12°C, lowered by 1°C a day to 8°C using a chiller, and maintained at that temperature for 3 days. The water temperature was then increased by 1°C per day to 12°C using a heater. The control group were the fish that kept at 12°C at the beginning of the experiment; T1 represents the group that sampled on the first day when the water temperature reached 8 from 12°C; T2 represents the group that sampled when the fish had been kept at 8°C for 3 days; T3 represents the group sampled when the water temperature was increased to 12 from 8°C. The antioxidant abilities of the liver, muscle, and intestine of large yellow croaker at different temperatures and times were determined, and the expression of HSP70 and HSP90 in the liver as well as the changes in intestinal microbiota were investigated. The results showed that the activities of SOD, CAT, GSH-Px, and MDA content increased significantly when the water temperature decreased from 12 to 8°C, significantly higher than those in the control group. The gene expression levels of HSP70 and HSP90 in the liver of large yellow croaker significantly increased under low temperature stress and were significantly higher than those in the control group. The diversity and abundance of intestinal microbiota of large yellow croaker were altered when the water temperature was maintained at 8°C, although the change was not obvious. Proteobacteria, Firmicutes, and Bacteroidetes were the dominate phyla in both the 12 and 8°C groups, and the temperature variation did not change the functional pathways of the microbiota. In conclusion, the acute temperature variation affected the antioxidant ability and heat shock protein expression of large yellow croaker but did not affect the diversity or abundance of the intestinal microbiota. These results will provide a theoretical basis for studying the mechanisms of large yellow croaker overwintering and adaptation to low temperatures.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2020
Coral Morphology Portrays the Spatial Distribution and Population Size-Structure Along a 5–100 m Depth Gradient

Netanel Kramer, Raz Tamir, Raz Tamir et al.

Population size structure provides information on demographic characteristics, such as growth and decline, enabling post-hoc assessment of spatial differences in susceptibility to disturbance. Nevertheless, very few studies have quantified size data of scleractinian corals along a shallow-mesophotic gradient, partly because of previously inaccessible depths. Here, we report the coral size-frequency distributions at the morphology level (six growth forms) and at the species level for ten representative locally abundant species along a broad depth gradient (5–100 m) in the Gulf of Eilat/Aqaba (GoE/A). A total of 18,865 colonies belonging to 14 families and 45 genera were recorded and measured over four reef sites. Colonies were found to be 11.2% more abundant at mesophotic (40–100 m; 55.6%) depths compared with shallow (5–30 m; 44.4%). The coral taxa exhibited heterogeneity in their size-structure, with marked differences among depths, morphological growth forms, and species. Branching and corymbose corals were more prevalent in shallow waters, while encrusting and laminar forms comprised the majority of mesophotic corals. Nevertheless, massive morphology was the most abundant growth form across all sites and depths (39%), followed by laminar (26%) and encrusting (20%). Corymbose corals (primarily Acroporidae) revealed constrained size at all depths; with the lack of small-size groups indicating populations at risk of decline. Depth-generalist species belonging to massive and laminar morphologies generally exhibited a larger colony size at the mesophotic depths, but were typified by a higher number of small colonies. Furthermore, we refute the widely and long-accepted assertion that Stylophora pistillata is the most abundant coral in the northern GoE/A, and assert that Leptoseris glabra is the one. Here, we provide a baseline for future monitoring of coral population structures, insights to recent ecological dynamics, retrospective assessment of coral community recovery following disturbances and grounds for conservation assessments and management actions.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2020
The Risky Decrease of Fishing Reference Points Under Climate Change

Morgane Travers-Trolet, Pierre Bourdaud, Mathieu Genu et al.

In Europe, implementation of sustainable fisheries management has been reinforced in the latest common fisheries policy, and presently marine fish stocks are mostly managed through assessment of their exploitation and ecological status compared to reference points such as Maximum Sustainable Yield (MSY). However, MSY and its associated fishing mortality rate FMSY are sensitive to both stock characteristics and environment conditions. In parallel, climate change impacts are increasingly affecting fish stocks directly and indirectly but might also change the exploitation reference points and the associated level of catch. Here we explored the variability of MSY reference points under climate change by using a multi-species model applied to the Eastern English Channel, a highly exploited semi-continental sea. The spatial individual-based OSMOSE explicitly represents the entire fish life cycle of 14 species interacting through size-based opportunistic predation. The model was first parameterized and run to fit the historical situation (2000–2009) and then used to assess the ecosystem state for the 2050–2059 period, using two contrasting climate change scenarios (RCP 4.5 and RCP 8.5). For each condition, a monospecific MSY estimation routine was performed by varying species fishing mortality independently and allowed estimation of reference points for each species. The FMSY estimated with OSMOSE were mostly in accordance with available values derived from stock assessment and used for fishing advice. Evolution of reference points with climate change was compared across species and highlighted that overexploited cold-water species are likely to have both MSY and FMSY declining with climate warming. Considering all species together, MSY under RCP scenarios was expected to be higher than historical MSY for half of them, with no clear link with species temperature preferences, exploitation status or trophic level, but in relation with expected change of species biomass under climate change. By contrast, for 80% of cases FMSY projections showed consistent decreasing pattern as climate conditions changed from historical to RCP scenarios in the Eastern English Channel. This result constitutes a risk for fisheries management, and anticipation of climate change impacts on fish community would require targeting a smaller fishing mortality than FMSY to ensure sustainable exploitation of marine stocks.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2020
Do Alternative Dispute Resolution (ADR) and Track Two Processes Support Transboundary Marine Conservation? Lessons From Six Case Studies of Maritime Disputes

Yael Teff-Seker, Yael Teff-Seker, Peter C. Mackelworth et al.

By definition, marine protected areas (MPAs) and other effective area-based conservation measures (OECMs) address spatial aspects of the ecological processes and marine features. Such a requirement is especially challenging in areas where there is no clearly defined jurisdiction. However, in these areas, assigning sovereignty and rights can be achieved through bilateral or multilateral agreements, or with the use of alternative dispute resolution (ADR) tools such as mediation and arbitration. In some cases, states may engage in transboundary marine conservation initiatives to provide an entry point to enable wider collaboration. These processes can also evolve into a form of ‘environmental peacebuilding’ while ideally maintaining ecosystem functioning and resilience as a core goal. Conversely, MPAs and OECMs can also be used to assert maritime sovereignty rights over disputed waters, under the pretext of conserving marine habitats. This paper identifies emerging issues of conflict resolution and their interaction with transboundary marine conservation. While ADR focuses on negotiations and facilitated processes between state representatives (“track one diplomacy”), we also discuss other forms and levels of marine environmental peacebuilding and dispute resolution, particularly those between civil society organizations (“track two diplomacy”). The six case studies presented highlight areas of recent maritime conflict or border disputes in the Mediterranean Sea, the Red Sea, the West Indian Ocean, the Korean West Sea and the South China Sea. In all cases, high ecological value, vulnerable ecosystems, and the need to conserve ecosystem services provide a shared interest for cooperation despite on-going diplomatic difficulties. The strategies used in these cases are analyzed to determine what lessons might be learned from cross-border collaborative marine initiatives in situations of territorial dispute. The use of ADR tools and their ability to support joint marine initiatives are examined, as well as how such initiatives contribute to formal border negotiations. Other forms of inter-state dialogue and cooperation between local or civil organizations, circumventing formal treaties and negotiations between state leaders (‘track two’) are also investigated. Finally, other influencing factors, including third-party involvement, stakeholder interests, power dynamics, economic context, and socio-cultural aspects, are considered.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2020
More Than Expected From Old Sponge Samples: A Natural Sampler DNA Metabarcoding Assessment of Marine Fish Diversity in Nha Trang Bay (Vietnam)

Marta Turon, Carlos Angulo-Preckler, Adrià Antich et al.

Sponges have recently been proposed as ideal candidates to act as natural samplers for environmental DNA due to their efficiency in filtering water. However, validation of the usefulness of DNA recovered from sponges to reveal vertebrate biodiversity patterns in Marine Protected Areas is still needed. Additionally, nothing is known about how different sponge species and morphologies influence the capture of environmental DNA and whether biodiversity patterns obtained from sponges are best described by quantitative or qualitative measures. In this study, we amplified and sequenced a vertebrate specific 12S barcode with a set of universal PCR primers (MiFish) for metabarcoding environmental DNA from fishes, to unveil fine-scale patterns of fish communities from natural-sampler DNA retrieved from 64 sponges (16 species) located in eutrophic and well-preserved coral reefs in Nha Trang Bay (central Vietnam). Ninety tropical fish species were identified from the sponges, corresponding to one third of the total local ichthyofauna reported from previous extensive conventional surveys. Significant differentiation in fish communities between eutrophic and well-preserved environments was observed, albeit eutrophication only explained a modest proportion of the variation between fish communities. Differences in efficiency of capturing fish environmental DNA among sponge species or morphologies were not observed. Overall, the majority of detected fish species corresponded to reef-associated small-sized species, as expected in coral reefs environments. Remarkably, pelagic, migratory, and deep-sea fish species were also recovered from sponge tissues, pointing out the ability of sponge natural sampled DNA to detect fishes that were not permanently associated to the biomes where the sponges were sampled. These results highlight the suitability of natural samplers as a cost-effective way to assess vertebrate diversity in hyper-diverse environments.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2019
Fifty shades of red: Lost or threatened bryophytes in Africa

Jacques van Rooy, Ariel Bergamini, Irene Bisang

Background: A Red List of threatened bryophytes is lacking for Africa. The International Union for Conservation of Nature (IUCN) Species Survival Commission (SSC) Bryophyte Specialist Group has recently launched the ‘Top 10 Initiative’ to identify the 10 species on each continent that are at highest risk of extinction. Objectives: The main aim of this paper was to highlight some of the lost or strongly threatened bryophyte species in sub-Saharan Africa and the East African islands and to draw up a Top 10 list for Africa. Method: Lost or threatened species have been identified with the help of experts on the bryoflora of Africa, global and regional Red Lists and taxonomic literature. Each species on this candidate list is discussed at the hand of its taxonomy, distribution, habitat, threat and current global or regional Red List status as far as previously assessed. Results: Fifty bryophyte species, representing 40 genera and 23 families, have been identified as Top 10 candidates. Of these, 29 are endemic to Africa and 21 are restricted to the East African islands. The majority of the candidate species occur in one of eight ‘biodiversity hotspots’ with most species (19) in the Madagascar and the Indian Ocean Islands hotspot. Conclusion: This is the first list of lost or threatened bryophytes for Africa and the first Top 10 list of the IUCN Bryophyte Specialist Group. It represents an important step towards regional and global Red List assessment of bryophytes, thus meeting the targets of the Updated Global Strategy for Plant Conservation 2011–2020 and priorities of The Shenzhen Declaration on Plant Sciences.

General. Including nature conservation, geographical distribution
DOAJ Open Access 2018
Retention of radiotransmitters tail‐mounted on 6 bird species

Richard A. Stanton Jr., Alicia D. Burke, Kaylan M. Carrlson et al.

ABSTRACT Radiotransmitters can be tail‐mounted using cyanoacrylate glue and an accelerant rather than using a harness. Tail‐mounted transmitters are dropped or shed when the rectrices molt, which may reduce transmitter effects while providing retention times sufficient for most research objectives. However, retention times of tail‐mounted transmitters for birds are insufficiently described, and bias from not following all birds until transmitters are shed has been ignored. We studied transmitter retention of 106 birds of 6 species in the United States of America, 2010–2013, using direct observations and survival modeling based on radiotelemetry tracking. Cox proportional hazard survival models predicted median transmitter retention times from 4 to 53 days, depending on species. Our results suggest that researchers should anticipate premature (i.e., <30 days) tag loss rates from 15% to 38% for adult birds, and adjust permit and funding applications accordingly. However, predicted premature tag loss approached 100% for independent juvenile birds, which frequently appeared to disperse long distances, leading to few or no failure events to inform models. Overall, our results provide guidance for the design of future telemetry studies while demonstrating that tail‐mounting transmitters can yield adequate data for a variety of research objectives. © 2018 The Wildlife Society.

General. Including nature conservation, geographical distribution
DOAJ Open Access 1973
A retractable barb needle for drug darts

G.L. van Rooyen, P.J. de Beer

The mechanism and action of a new retractable barbneedle for drug darts are described. This dart needle is particularly successful in obviating unnecessary flight reactions andtrauma in darted animals, and facilitates the complete injection of the drug dose before the barb is retracted and the dart is dislogded from the animal. The whole process is completed within a few seconds and the expended dart can usually be retrieved in the immediate vicinity where the animal was darted.

General. Including nature conservation, geographical distribution

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