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We examined the floristic composition and stand structure of tropical mountain forests containing two pine species, Pinus krempfii Lecomte and Pinus dalatensis Ferré, on the Da Lat Plateau in southern Vietnam. A total of 92 tree species were identified, and the greatest species richness at the family level was found in Lauraceae and Fagaceae. Both pine species grew to more than 25 m in height and spread their crowns over the continuous canopy layer. Under crowns of P. krempfii, Castanopsis chinensis, Trigonobalanus verticillata, Engelhardia roxburghiana, and Dendropanax hainanensis constituted the continuous canopy layer. Under crowns of P. dalatensis, pioneer species such as Schima wallichii, Exbucklandia populnea, and Pentaphylax euryoides along with gymnosperms such as Dacrycarpus imbricatus and Dacrydium elatum constituted the continuous canopy layer. Juveniles of P. krempfii were prevalent on the forest floor, but juveniles of P. dalatensis were scarce. We suggest that two pine species have different regeneration requirements related to disturbance and soil condition.
The Tasmanian devil (Sarcophilus harrisii (Boitard)) is an endangered carnivorous marsupial, limited to the islands of Tasmania in southern Australia. The parasites of the Tasmanian devil are understudied. This study aimed to increase the knowledge of the nematode fauna of Tasmanian devils. Ten Tasmanian devils were examined for parasites from northern and southern Tasmania. Nematodes that were collected were morphologically characterized as two separate species. Molecular sequencing was undertaken to verify the identity of these species. A new genus and species of oxyurid nematode was collected from a single Tasmanian devil from the northern part of Tasmania. The nematode is differentiated from oxyurids described from other Australian amphibians, reptiles and marsupials by the characters of the male posterior end – that is, in having three pairs of caudal papillae, two pairs peri-cloacal, one large pair post-cloacal, a long tapering tail, a stout spicule and a gubernaculum and accessory piece, as well as its much larger overall size. Molecular sequencing was unsuccessful. The remaining nematodes collected from the Tasmanian devil in this study were all identified as Baylisascaris tasmaniensis Sprent, 1970, through morphology and molecular sequencing. This paper presents the first description of a new genus and species of oxyurid nematode from the Tasmanian devil, Sarcophiloxyuris longus n. gen., n. sp. The need to undertake more sampling of the parasites of endangered hosts, such as the Tasmanian devil, to assist with a better understanding of their conservation management, is discussed.
This paper proposes some possibilities for thinking with a landscape as a pedagogical concept, inspired by posthuman theory. The idea of thinking with a landscape is enacted in the Australian Alps (AA), concentrating on the contentious environmental dilemma involving introduced horses and their management in this bio-geographical location. The topic of horses is of pedagogical relevance for place-responsive outdoor environmental educators as both a location-specific problem and an example of a troubling issue. The paper has two objectives for employing posthuman thinking. Firstly, it experiments with the alternative methodological possibilities that posthuman theory affords for outdoor environmental education, including new ways of conducting educational research. Secondly, it explores how thinking with a landscape as a pedagogical concept may help open ways of considering the dilemma that horses pose. The pedagogical concept is enacted through some empirical events which sketch human–horse encounters from the AA. These sketches depict some of the pedagogical conversations and discursive pathways that encounters can provoke. Such encounters and conversations are ways of constructing knowledge of the landscape, covering multiple species, perspectives and discursive opportunities. For these reasons, this paper may be of relevance for outdoor environmental educators, those interested in the AA or posthuman theorists.
Understanding the environmental drivers of demographic processes is a prerequisite for providing the evidence-based conservation guidance and management actions required to address management goals at population level. Human activities, to which most species are not adapted, are having an ever-increasing impact on the environment. Most policies and strategies focus on broad-scale conservation actions and disregard the fact that this type of action may not be adequate at local scale. In addition, even though the main conservation targets are well known, managers and practitioners lack an explicit framework in which to identify the varying requirements of site-specific conservation actions. Our aim was to provide an accurate tool for prioritizing specific local-scale conservation actions for endangered territorial birds. In this study we describe our proposed framework using a population of the endangered Bonelli’s Eagle Aquila fasciata as a case study. We identified the most relevant environmental drivers linked to demographic parameters (occupation, productivity and survival) at local scale shaping the dynamics of the Bonelli’s Eagle population in Catalonia (Spain). This information will be useful for designing specific local-scale conservation actions in eagles’ territories with low demographic parameter values. This is a good example of how applied research and achievable conservation practices are applicable to other Bonelli’s eagle populations and to those of other endangered raptors.
The Black-capped Petrel or Diablotin Pterodroma hasitata has a fragmented and declining population estimated at c.1,000 breeding pairs. On land, the species nests underground in steep ravines with dense understorey vegetation. The only confirmed breeding sites are located in the mountain ranges of Hispaniola in the Caribbean, where habitat loss and degradation are continuing threats. Other nesting populations may still remain undiscovered but, to locate them, laborious in situ nest searches must be conducted over expansive geographical areas. To focus nest-search efforts more efficiently, we analysed the environmental characteristics of Black-capped Petrel nesting habitat and modeled suitable habitat on Hispaniola using openly available environmental datasets. We used a univariate generalized linear model to compare the habitat characteristics of active Black-capped Petrel nests sites with those of potentially available sites (i.e. random pseudo-absences). Elevation, distance to coast, and the influence of tree cover and density emerged as important environmental variables. We then applied multivariate generalized linear models to these environmental variables that showed a significant relationship with petrel nesting activity. We used the top performing model of habitat suitability model to create maps of predicted suitability for Hispaniola. In addition to areas of known petrel activity, the model identified possible nesting areas for Black-capped Petrels in habitats not previously considered suitable. Based on model results, we estimated the total area of predicted suitable nesting habitat for Black-capped Petrels on Hispaniola and found that forest loss due to hurricanes, forest fires, and encroachment from agriculture had severely decreased availability of predicted suitable habitat between 2000 and 2018.
Globally, more and more species are at risk of extinction as the environment and climate change. Many of these species require long-term management to persist - they are conservation-reliant. The magnitude of this challenge requires a rethinking of how conservation priorities are determined and a broader societal commitment to conservation. Choices need to be made about which species will be conserved, for how long, and by whom. This volume uses case studies and essays by conservation practitioners from throughout the world to explore what conservation reliance is and what it means for endangered-species management. Chapters consider threats to species and how they are addressed, legal frameworks for protecting endangered species, societal contexts and conflicts over conservation goals, and how including conservation reliance can strengthen methods for prioritizing species for conservation. The book concludes by discussing how shepherding nature requires an evaluation of societal values and ethics.
The description of the movements and habitat preference of marine fishes is essential to understand their biology and in the evaluation of commercially exploited species and the conservation of endangered ones. In this regard, little is known about the movements of the totoaba (Totoaba macdonaldi), despite its being listed as critically endangered and having been a relevant fishery resource in the past century in Mexico. Totoaba is a fish species endemic to the Gulf of California characterized by late maturation, prolonged life and annual reproduction. Totoaba has maintained its known historical distribution range, although its movements and habitat occupancy in the water column have remained poorly understood. The present study describes, for the first time and at a daily fine scale, the vertical movements and habitat preferences of the totoaba in the Upper Gulf of California. Pop-up satellite archival tags (PSATs) were used to record depth and temperature at 4-minute intervals. Ten individuals were caught and tagged in May 2016 in the Upper Gulf of California and Colorado River Delta Biosphere Reserve. All PSATs were either prematurely released or lost. Data derived from two recovered tags that saved data for 43 and 75 tracking days, respectively, were analysed. The results showed that tagged fishes moved southward to the vicinity of Angel de la Guarda Island; these are consistent with spatial displacement patterns reported in the literature, with a linear displacement of 223 km from deployment to pop-up sites. Fish spent 47% of the time within a depth range of 25–35 m. Depth increased to 70 m for one fish in early summer (late June). The preferred temperature of fishes ranged between 21–23°C. A generalized linear model revealed that vertical movement was influenced by temperature. The vertical displacement of the totoaba shows a diurnal variation that may be associated with the distribution of its prey. Further work is needed to test this hypothesis with a larger number of organisms.
Once widespread throughout the Black and Mediterranean Seas and the coasts of north Africa, the Endangered Mediterranean monk seal Monachus monachus has disappeared throughout most of its original range. In Cyprus evidence suggests that the species became effectively extinct at the end of the 20th century. Following an increase of seal sightings around the island, a monitoring programme was established in 2009 to evaluate the status of the species. During 2009–2018, using field surveys, photographs from camera traps and an information network, we recorded an increasing number of seal sightings, and the birth of several pups, indicating the permanent presence of the species on the island. This is the first recorded re-establishment of a Mediterranean monk seal population in an area of its former range following near eradication.
In response to the CITES ban on trade in elephant ivory, mammoth ivory began to be produced in post-Soviet Russia. We investigate how this substitute to elephant ivory has affected the poaching of elephants. We argue that the early success of the 1989 ivory ban at increasing the African elephant population was driven in part by increasing supply of mammoth ivory. The more recent increases in poaching appear to be driven by increasing demand and falling African institutional quality. We find that absent the 80 tonnes of Russian mammoth ivory exports per annum 2010–2012, elephant ivory prices would have doubled from their $ 100 per kilogram level and that the current poaching level of 34,000 elephants per year may have increased by as many as 55,000 elephants per year on a population of roughly half a million animals.
Traditionally the vulnerability of threatened species to extinction has been assessed by studying their environment, genetics and population dynamics. A more comprehensive understanding of the factors promoting or limiting the long-term persistence of threatened species could be achieved by conducting an analysis of their functional responses to changing environments, their ecological interactions, and their role in ecosystem functioning. These less traditional research areas can be unified in a trait-based approach, a recent methodological advance in ecology that is being used to link individual-level functions to species, community and ecosystem processes to provide mechanistic explanations of observed patterns, particularly in changing environments. We illustrate how trait-based information can be translated into well-defined conservation strategies, using the example of Dioon sonorense, an Endangered cycad endemic to north-western Mexico. Scientific information yielded by trait-based research, coupled with existing knowledge derived from well-established traditional approaches, could facilitate the development of more integrative conservation strategies to promote the long-term persistence of individual threatened species. A comprehensive database of functional traits of threatened species would be of value in assisting the implementation of the trait-based approach.
This paper examines the petroleum industry's willingness to participate in conservation agreements for the lesser prairie chicken, a candidate for listing under the Endangered Species Act (ESA). Voluntary conservation agreements with assurances (VCAAs) can incentivize habitat conservation and sustain economic development. Using data on oil and natural gas wells in Kansas and Oklahoma, I develop a discrete choice model to examine company preferences for locating wells and participating in VCAAs for the lesser prairie chicken. Participation in VCAAs is low, but I find participating wells are concentrated in areas with the most crucial habitat.
The genus Acanthogobius of gobiioid fish has been reported for six species from East Asia, and inhabits estuarine and coastal waters. Within this genus, Acanthogobius insularis is an endangered and endemic goby in the Amami-oshima and Okinawa-jima Islands, southern Japan, and its range is restricted to the lowermost course of a few river basins. Basic knowledge on this species is scarce in spite of its vulnerable conservation status. The purpose of this study was to elucidate the life history of A. insularis. Monthly sampling was conducted at five stations in the Taiho River, Okinawa-jima Island, from November 2014 to November 2015. Monthly standard length (SL) distributions were unimodal except in April during the recruiting period, suggesting that A. insularis is an annual species. Analysis of the gonadosomatic index and histological observations of the ovaries revealed that this species spawns from January to May. The beginning of the spawning season seems to be related to a decline in water temperature in December. Growth rates appeared to be lower from April to December and higher in winter months. From monthly collections, A. insularis was found to move upstream with growth, and gather at spawning grounds during the reproductive season. Acanthogobius insularis might be threatened by increasing water temperature due to climate change, since low water temperatures appear to be important for their reproduction and growth. Moreover, habitat diversity, from tidal flats for recruiting grounds to upstream sites with cobbles for spawning, is needed to complete their life cycle, and should be conserved.
Germination studies at the community level are crucial for understanding and predicting changes in species distribution patterns, particularly in endangered plant communities. We investigated the effects of dry (11–25% relative humidity) and freezing (–18°C) storage conditions, phylogeny and plant life-history traits (life-form, life-span, microhabitat and seed dispersal mode) on seed germination percentage (GP) and time to reach 50% germination (T50) of 53 species native to pine rocklands in South Florida, USA, a globally critically imperiled ecosystem. Most species we studied (68%) withstood dry and freezing storage conditions and thus ex situ seed banking can assist their long-term conservation. Bayesian mixed effect models revealed that there was a significant phylogenetic signal in GP and T50 across species. Life-history covariates did not explain significant additional variation in GP in models controlling for the phylogenetic relationships among species. T50 differed among species with contrasting dispersal modes, with animal-dispersed seeds exhibiting more delayed germination than wind-dispersed or unassisted seeds. Differential germination responses across species with different seed dispersal modes have implications for potential shifts in species composition under disturbance and climate change. Thus, knowledge of species-relatedness and some life-history traits such as seed dispersal mode can significantly assist management decisions regarding seed storage and conservation of subtropical endangered plants.
Fungal spores, especially those of coprophilous fungi, are present in dung middens of Rhinoceros unicornis (greater one-horned rhinoceros) in both forest and grassland areas of the Kaziranga National Park, India. The presence of coprophilous fungi on rhino dung, chiefly Sporormiella, Saccobolus, Ascodesmis, Cercophora, and Sordaria, is documented for the first time. The Sporormiella–Ascodesmis–Saccobolus assemblage is abundant and characterizes the rhino dung in forest and grassland areas. The presence of coprophilous fungi spores allows for an examination of the relationship between rhinoceros ecology and the flora and other fauna in the region. The overall dataset is useful in interpreting the present and past distribution of rhino and other associated animals based on the relative abundance of different types of coprophilous fungi spores and their relationship to paleoherbivory and paleoecology in India and adjoining areas.
The East Asian–Australasian flyway contains some of the most threatened habitats in the world, with at least 155 waterbird species reliant on the tidal habitats it comprises. The black-faced spoonbill (Platalea minor) is an iconic endangered species distributed across the coast of East Asia. Its population suffered a severe decline into the 1990s, but extensive monitoring and conservation interventions have aided a substantial recovery of the species. We used a population viability analysis based on data collected over the past two decades in conjunction with species distribution models to project spatially explicit models of population change for the next 35 years. Over nearly all scenarios of habitat loss and climate change, the global spoonbill population was projected to increase in the short-term due to low population numbers likely well below current population carrying capacities. However, climate change and habitat loss together threaten the recovery of the spoonbill population such that, by 2050, population declines are apparent as a consequence of these cumulative impacts. These threats are also cryptic and represent a challenge to the conservation of species recovering from anthropogenic impacts; observed population increases can hide large reductions in habitat suitability that threaten the long-term viability of species.
Feral swine Sus scrofa have been implicated as a major threat to sensitive habitats and ecosystems as well as threatened wildlife. Nevertheless, direct and indirect impacts on threatened species (especially small, fossorial species) are not well documented. The decline of the U.S. federally endangered reticulated flatwoods salamander Ambystoma bishopi, categorized as Vulnerable on the IUCN Red List, has been rapid and there are few remaining breeding locations for this species. The flatwoods salamander depends on complex herbaceous vegetation in all life stages, including eggs, larvae and adults. Historically sets of hog tracks have been observed only occasionally in the vicinity of monitored reticulated flatwoods salamander breeding wetlands, and damage to the wetlands had never been recorded. However, during the autumn–winter breeding season of 2013–2014 we observed a large increase in hog sign, including extensive rooting damage, in known flatwoods salamander breeding wetlands. Our objective was to assess the amount of hog sign and damage in these wetlands and to take corrective management actions to curb additional impacts. Of 28 wetlands surveyed for hog sign, presence was recorded at 68%, and damage at 54%. Of the 11 sites known to be occupied by flatwoods salamanders in 2013–2014, 64% had presence, and 55% had damage. We found that regular monitoring of disturbance in wetland habitats was a valuable tool to determine when intervention was needed and to assess the effectiveness of intervention. Habitat damage caused by feral hogs poses a potentially serious threat to the salamanders, which needs to be mitigated using methods to control and exclude hogs from this sensitive habitat.
Despite increasing support for conservation efforts, humans exert strong negative forces on nature and disagree over the management of these effects. Conflicts over conservation policy may reflect evolving opinions about how people ought to conserve species and whether to intervene in various processes. To understand public preferences for conservation in the USA, we measured support for various strategies in five case studies, where we pitted one species against another in simplified but realistic scenarios. Among our online convenience sample of 1040 participants, we found the majority of participants favoured habitat protection in all but one case, and there was little acceptance of lethal control across all cases. The results reveal that habitat protection preferences positively relate to considerations of moral principles and ecosystems and negatively relate to economic and practical considerations. Older, conservative and male participants were less likely to support habitat protection and more likely to support no action. The results suggest broad support for holistic nature conservation that benefits both people and nature and highlight areas where current wildlife management may not align with public preferences. Controversy may continue until wildlife management policies are consistent with societal values and address moral and ecosystem considerations at multiple levels.
The movement and activity patterns of the nurse shark, Ginglymostoma cirratum, a vulnerable species off Brazil, were investigated using mark-recapture and acoustic telemetry at an oceanic insular Marine Protected Area, the Fernando de Noronha Archipelago, Brazil. A total of 93 sharks were captured and tagged, ranging from 82 to 265 cm of total length (TL). Nurse sharks were captured throughout the year, and all life-stages used the insular shelf. Fifteen sharks (16% of the total) were recaptured after periods at liberty ranging from 3.5 h to 705 days, and the distances between tag and recapture locations ranged from 0.07 to 3.5 km. Site fidelity and movements of 10 sharks ranging from 107 to 265 cm TL were investigated for 18 months with an array of automated telemetry receivers. The mean period of detection of the monitored sharks was 66 days, ranging from 13 to 119 days. One individual 158 cm TL was monitored with active tracking for 17 days, with distances between daily locations ranging from 0.84 to 3.32 km, exhibiting movements similar to those of sharks monitored by automated telemetry. Despite remaining motionless or exhibiting short range movements for several hours or days, nurse sharks can be relatively wide-ranging, and protected areas alone cannot be the only conservation measure used to protect this species, which requires a set of protective measures, including fisheries management.
Ecologists examine diet composition in order to assess the spatial and temporal variations in interactions between species, the impact of different species traits on the ecological network structure, and the long-term effects of the removal of different species by small-scale fisheries. In this study, our goal was to compare the diets of silky sharks (Carcharhinus falciformis) and scalloped hammerhead sharks (Sphyrna lewini) off the south-west coast of Mexico in order to infer their diet preferences and spatial distributions. We sampled 164 S. lewini (96 stomachs had food, 68 were empty) and 183 C. falciformis (30 stomachs had food, 153 were empty) in Puerto Madero, Chiapas in 2011. The large number of empty stomachs may be the result of using longline fishing gear, which causes high stress resulting in regurgitation. Based on the index of relative importance (%IRI), the fish Chloroscombrus orqueta (IIR = 27.7%) was the most important species in the diet of S. lewini, while the squid Dosidicus gigas (IIR = 34%) was the primary prey of C. falciformis. Levin's index (Bi) and Shannon's index (H′) confirm that both sharks are generalists, as in other regions. The trophic levels of S. lewini (TL = 4.1) and C. falciformis (TL = 4.2) are characteristic of tertiary consumers; meanwhile, the Morisita–Horn index indicates low interspecific overlap between all categories. These results confirm that these two sharks have different foraging preferences or movement patterns; thus, there is no trophic overlap between species as they play unique roles in the ecological network off the south-west coast of Mexico.
To avoid extinction of rare species in regions of active environmental change, strategic approaches are needed to manage remaining habitat. When observations of dispersal or metapopulation information are not available, habitat connectivity simulations may offer a valuable alternative source of information to assess threats and evaluate conservation options. For the Critically Endangered San Martin titi monkey (Callicebus oenanthe) in north central Peru, an updated distribution model was generated and land cover in the heavily deforested northern range of the species was mapped. The value of remaining forest fragments was characterized and threats from future land use change were assessed using complementary connectivity models. It is estimated that the species range is less than 14 000 km2. Remote sensing analysis reveals that at least 34% of lowland forest in the northern range has been lost, while nearly 95% of remaining habitat fragments are likely too small to support viable populations and less than 8% of this habitat lies within conservation areas. Areas with the highest modelled connectivity comprise only 10% of the remaining forest in the northern range and small patches may contribute disproportionately to movement; these lands represent opportunities for conservation and reforestation to prevent potentially significant impacts from future mining and urban development. This study prioritized remaining suitable habitat patches using modelled connectivity and local knowledge to gain insight into the status of an understudied species. This approach offers a relatively rapid method to identify potential land use conflicts, and to further focus research and locally appropriate conservation.