We studied the sperm whale Physeter macrocephalus in the Colombian Caribbean by combining data from our offshore surveys of behaviour, encounter rate, group structure and density with data from the literature. We describe for the first time the potential distribution of sperm whales in the Colombian Caribbean, using sighting and acoustic data obtained during our surveys, published information, and opportunistic encounters during 1988–2020. We conducted surveys on seismic vessels over 703 days during 2011–2016, covering an area of 68,904 km2. We recorded 98 individuals in a total of 50 groups, a density of 1.42 individuals per 1,000 km2. To determine the potential distribution of the species, we built Maxent models with uncorrelated environmental variables at five depths (from the surface to c. 2,000 m). The model for 1,000 m depth had the best performance, with areas of high probability of occurrence of sperm whales in the south and north-east Colombian Caribbean over the shelf break to waters up to c. 3,000 m deep, at a median distance of 107 km from the coast, and near the Archipelago of San Andrés, Old Providence and Saint Catherine in the north-west. This area may be an important tropical habitat for sperm whales, in which they socialize, rest, breed and feed. Our study underlines the importance of monitoring marine mammals offshore and describes the potential distribution of sperm whales in the Colombian Caribbean, supporting conservation actions for this Vulnerable species, which is currently facing several threats in this region.

The Mediterranean monk seal Monachus monachus, categorized as Endangered on the IUCN Red List, comprises 600–700 individuals in the eastern Mediterranean Sea and eastern Atlantic Ocean. Habitat degradation is a severe threat to the species. In 2016 and 2017, coastline surveys were conducted in Gökova Bay, south-west Turkey, to identify suitable monk seal habitat. A significant factor hindering recovery of the monk seal population of this Turkish coast and the nearby Greek islands is the limited number of marine caves suitable for resting and/or pupping. We identified four caves as possible monk seal resting and pupping caves. An additional cave with all essential features for seal usage except a ledge was also identified. An artificial ledge was built in this cave in July 2019 and seal usage was monitored by camera trap until September 2020. A total of 405 camera-trap events were analysed to examine presence of any monk seals on the ledge, and to understand the purpose (resting and/or pupping), frequency of use, sex and age group of any individuals using the cave. One juvenile used the cave four times for resting (420 minutes in total), predominantly nocturnally. This is the first construction of a dry ledge in a cave of this kind for monk seals. The camera recordings suggest this approach could provide habitat for this species in areas where there is insufficient dry protected area on land.

Knowledge of the abundance and distribution of species is important for designing and prioritizing conservation and management activities. Despite numerous existing studies on the distribution and status of sea turtles, we still lack knowledge about certain populations, especially in Angola, which is considered to be the southernmost range of nesting sea turtles in the eastern Atlantic. This study provides an overview of the status, size and distribution of the olive ridley sea turtle Lepidochelys olivacea population nesting along the coast of Angola, and its relevance in the context of other olive ridley turtle nesting populations in the Atlantic. Aerial and ground surveys were conducted along 1,410 km of Angolan coastline and daily beach monitoring over 53.9 km of seven permanent study sites at a range of latitudes during 2011–2020. Angola hosts the largest olive ridley turtle nesting population in the Atlantic, and the largest non-arribada population globally. Although the population appeared relatively stable, the pressures from various threats on land (e.g. consumption of turtles and eggs) and at sea (captures in fishing gear) necessitate the development of a comprehensive management plan, improved and strengthened legislation and law enforcement, and a cohesive approach to conserving all sea turtle species in Angola.

Few marine taxa have been comprehensively assessed for their conservation status, despite heavy pressures from fishing, habitat degradation and climate change. Here we report on the first global assessment of extinction risk for 300 species of syngnathiform fishes known as of 2017, using the IUCN Red List criteria. This order of bony teleosts is dominated by seahorses, pipefishes and seadragons (family Syngnathidae). It also includes trumpetfishes (Aulostomidae), shrimpfishes (Centriscidae), cornetfishes (Fistulariidae) and ghost pipefishes (Solenostomidae). At least 6% are threatened, but data suggest a mid-point estimate of 7.9% and an upper bound of 38%. Most of the threatened species are seahorses (Hippocampus spp.: 14/42 species, with an additional 17 that are Data Deficient) or freshwater pipefishes of the genus Microphis (2/18 species, with seven additional that are Data Deficient). Two species are Near Threatened. Nearly one-third of syngnathiformes (97 species) are Data Deficient and could potentially be threatened, requiring further field research and evaluation. Most species (61%) were, however, evaluated as Least Concern. Primary threats to syngnathids are (1) overexploitation, primarily by non-selective fisheries, for which most assessments were determined by criterion A (Hippocampus) and/or (2) habitat loss and degradation, for which assessments were determined by criterion B (Microphis and some Hippocampus). Threatened species occurred in most regions but more are found in East and South-east Asia and in South African estuaries. Vital conservation action for syngnathids, including constraining fisheries, particularly non-selective extraction, and habitat protection and rehabilitation, will benefit many other aquatic species.

We describe the population of the Еndangered sea otter Enhydra lutris on Urup Island, one of the main wildlife refuges in the southern Kuril Islands of Russia. We reviewed historical and local reports of the sea otter, identified its habitat around the island, and surveyed the coastal waters of the island in 2019. Sea otters were numerous on Urup Island in the past but were hunted excessively and almost exterminated by the 1950s. Since then, sea otter populations have increased, and as the island is almost uninhabited we expected otters to be numerous. This was not the case, and we estimated the total population to be 363 ± SE 126 individuals. Our observation of two skinned carcasses on the shore suggests the low numbers are a result of poaching for the illegal fur trade. The case of Urup Island demonstrates that sea otters require active conservation, as even on a remote island they remain threatened. Establishment of protected areas would be an effective conservation measure for this species, although the suppression of demand for sea otter fur is of the greatest importance.

The Endangered Mediterranean monk seal Monachus monachus is one of the most threatened marine mammals. Across Cyprus, suitable habitat and presence of monk seals is well documented and, recently, camera-trap surveys in Southern Cyprus found there to be pupping. We present results of the first camera-trap surveys in Northern Cyprus spanning the pupping period. Four adult/subadults and three pups were identified in three of eight caves monitored with camera traps. One site on the north-west of the island supported at least three adult/subadult seals and pupping occurred there in 3 consecutive years. The breeding and resting sites identified require urgent conservation to manage threats of disturbance, coastal development and fisheries bycatch. To determine the size of this population, a long-term survey with greater and more continuous coverage is required.

Protecting marine biodiversity and ensuring sustainable use through a seascape approach is becoming increasingly widespread in response to the ecological, social and institutional challenges of scaling ocean management. A seascape approach means clustering spatial management measures (marine protected areas) based around the principles of ecological connectivity, and developing or enhancing collaborative governance networks of relevant stakeholders (managers, community groups, non-governmental organizations) based around the principles of social connectivity. As with other large-scale approaches to marine management, there is minimal evidence of long-term impact in seascapes. This study uses a theory-based, participatory impact evaluation to assess perceived changes attributed to the Atlántida seascape in Honduras (initiated in 2015), encompassing three well-established marine protected areas and the non-legally managed waters between them. Using an adapted most significant change method, 15 interviews with a representative subset of seascape stakeholders yielded 165 stories of change, the majority (88%) of which were positive. Enhanced social capital, associated with cross-sectoral collaboration, inter-site conflict resolution and shared learning, was the most consistently expressed thematic change (32% of stories). Although most stories were expressed as activity- or output-related changes, a small proportion (18%) were causally linked to broader outcomes or impact around increased fish and flagship species abundance as well as interconnected well-being benefits for people. Although minimal (and occasionally attributed to prior initiatives that were enhanced by the seascape approach), this impact evidence tentatively links seascapes to recent related research around the effectiveness of appropriately scaled, ecosystem-based and collaboratively governed marine management that balances strict protection with sustainable use.

A basic tenet of ecotourism is to enhance conservation. However, few studies have assessed its effectiveness in meeting conservation goals and whether the type of tourism activity affects outcomes. This study examines whether working in ecotourism changes the perceptions of and attitudes and behaviours of local people towards the focal species and its habitat and, if so, if tourism type affects those outcomes. We interviewed 114 respondents at four whale shark Rhincodon typus tourism sites in the Philippines to compare changes in perceptions of and attitudes and behaviours towards whale sharks and the wider marine environment. We found that the smaller scale tourism sites had greater social conservation outcomes than the mass or failed tourism sites, including changes in conservation ethics and perceptions of and attitudes and behaviours towards whale sharks and the ocean. Furthermore, of the three active tourism sites, the smallest site, with the lowest economic returns and the highest negative impacts on whale sharks prior to tourism activities, had the largest proportion of respondents who reported a positive change in perceptions of and attitudes and behaviours towards whale sharks and the ocean. Our results suggest that tourism type, and the associated incentives, can have a significant effect on conservation outcomes and ultimately on the ecological status of an Endangered species and its habitat.

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.

To summarize the state of knowledge of the Endangered Antillean manatee Trichechus manatus manatus in Hispaniola, which comprises the Dominican Republic and Haiti, I reviewed documentary archives from pre-Columbian times to 2013. Manatees were historically abundant in Hispaniola but were hunted for centuries for their meat and other body parts for diverse uses. By the end of the 19th century manatees had become relatively rare around the island. Nevertheless, manatees remain widespread along the coast and occasionally occupy freshwater habitats in the Dominican Republic. In Haiti recent manatee sightings were restricted to two coastal areas. Currently, the manatee population of Hispaniola is perceived to be declining. The most commonly reported threats to the species include hunting, entanglement in fishing gear, boat strikes and disturbance by boat traffic, pollution, and habitat degradation and destruction. In the Dominican Republic longstanding national laws and international agreements protect the species and its habitat, and past conservation actions have raised public awareness about the status of the manatee. In Haiti knowledge of manatees is extremely limited and the species is not legally protected. I propose country-specific and binational recommendations to improve the contemporary conservation of manatees in the Dominican Republic and Haiti.

Translocation and rehabilitation programmes are critical tools for wildlife conservation. These methods achieve greater impact when integrated in a combined strategy for enhancing population or ecosystem restoration. During 2002–2016 we reared 37 orphaned southern sea otter Enhydra lutris nereis pups, using captive sea otters as surrogate mothers, then released them into a degraded coastal estuary. As a keystone species, observed increases in the local sea otter population unsurprisingly brought many ecosystem benefits. The role that surrogate-reared otters played in this success story, however, remained uncertain. To resolve this, we developed an individual-based model of the local population using surveyed individual fates (survival and reproduction) of surrogate-reared and wild-captured otters, and modelled estimates of immigration. Estimates derived from a decade of population monitoring indicated that surrogate-reared and wild sea otters had similar reproductive and survival rates. This was true for males and females, across all ages (1–13 years) and locations evaluated. The model simulations indicated that reconstructed counts of the wild population are best explained by surrogate-reared otters combined with low levels of unassisted immigration. In addition, the model shows that 55% of observed population growth over this period is attributable to surrogate-reared otters and their wild progeny. Together, our results indicate that the integration of surrogacy methods and reintroduction of juvenile sea otters helped establish a biologically successful population and restore a once-impaired ecosystem.

The Vulnerable bumphead parrotfish Bolbometopon muricatum, a highly prized fishery resource worldwide, has experienced population declines throughout its geographical range. There is limited knowledge of the distribution and abundance of, and threats to, this fish in Indian waters, particularly for the Andaman and Nicobar Islands. To assess the species’ distribution and conservation status we conducted underwater surveys across 75 sites around 51 islands and interviewed 99 fishers across the Andaman and Nicobar archipelago. We recorded a total of 59 individual B. muricatum across nine sites from the northernmost island in the Andamans (Landfall Island) to the southernmost island in the Nicobars (Great Nicobar Island). Interviews revealed that most fishers (100% in Nicobar, 94% in Middle Andaman, 62% in South Andaman) had seen B. muricatum, and knowledge of the species is highest amongst spearfishers. Generalized linear models indicated that presence of marine protected areas and high live coral cover influenced the abundance and distribution of B. muricatum. The species' density seems to be naturally low in the archipelago. We discuss our findings in the light of protecting rare and threatened species, and recommend strengthening the existing marine protected areas in these islands.

Coastal ecosystems have been degraded by human activity over centuries, with loss of memory about past states resulting in shifted baselines. More recently conservation efforts have resulted in localized recoveries of species and ecosystems. Given the dynamism of ecosystem degradation and recovery, understanding how communities perceive long-term and recent changes is important for developing and implementing conservation measures. We interviewed stakeholders on three Caribbean islands and identified a shifted baseline with respect to the extent and degree of long-term declines in marine animal populations; stakeholders with more experience identified more species as depleted and key species as less abundant than those with less experience. Notably, the average respondent with < 15 years of experience listed no species as depleted despite clear evidence of declines. We also identified a phenomenon we call the policy placebo effect, in which interviewees perceived some animal populations as recently recovering following passage of new conservation legislation but in the absence of evidence for actual recovery. Although shifted baselines have a negative effect on conservation as they can lower recovery goals, the outcomes of a policy placebo effect are unclear. If the public prematurely perceives recovery, motivation for continued conservation could decline. Alternatively, perception of rapid success could lead communities to set more ambitious conservation goals.

Tun Mustapha Park, in Sabah, Malaysia, was gazetted in May 2016 and is the first multiple-use park in Malaysia where conservation, sustainable resource use and development co-occur within one management framework. We applied a systematic conservation planning tool, Marxan with Zones, and stakeholder consultation to design and revise the draft zoning plan. This process was facilitated by Sabah Parks, a government agency, and WWF-Malaysia, under the guidance of the Tun Mustapha Park steering committee and with support from the University of Queensland. Four conservation and fishing zones, including no-take areas, were developed, each with representation and replication targets for key marine habitats, and a range of socio-economic and community objectives. Here we report on how decision-support tools informed the reserve design process in three planning stages: prioritization, government review, and community consultation. Using marine habitat and species representation as a reporting metric, we describe how the zoning plan changed at each stage of the design process. We found that the changes made to the zoning plan by the government and stakeholders resulted in plans that compromised the achievement of conservation targets because no-take areas were moved away from villages and the coastline, where unique habitats are located. The design process highlights a number of lessons learned for future conservation zoning, which we believe will be useful as many other places embark on similar zoning processes on land and in the sea.

Birds are commonly entangled in long-line fisheries, and increases in long-line fishing activity have consistently caused declines in seabird populations. Environmental criminology would posit that the risk of such declines is greater in the case of illegal long-line fisheries, which are less likely to implement bycatch mitigation measures. To investigate this possibility we examined the overlap between data on illegal fishing and albatross at-sea occurrence ranges. Moderate correlations were found between mean exposure to illegal fishing and the Red List status of albatross species, but none were found between Red List status and total fishing pressure. A second analysis overlaid albatross at-sea occurrence ranges with long-lining data for the member countries of the Convention on Conservation of Southern Bluefin Tuna to compare the effect of exposure to legal and illegal hooks on Red List status. Lacking a better measure, Country A's hooks were used as a proxy for illegal hooks. Critically Endangered and Endangered species were 12 and 3.4 times more exposed to illegal hooks, respectively, than Near Threatened species, whereas there was no relationship between Red List status and exposure to legal hooks. Country-level analyses confirmed these findings, which provide evidence that illegal long-line fishing poses a particular threat to the survival of albatrosses. The findings suggest that the bird conservation lobby should work closely with fisheries authorities to tackle illegal fishing, and that research should identify the highest risk areas of overlap between illegal fishing and albatross at-sea ranges.

Despite the considerable expansion in the number and extent of marine protected areas during the past century, coverage remains limited amid concerns that many marine protected areas are failing to meet their objectives. New estimates of global marine protected area, based on the database maintained by Sea Around Us, revealed a degree of progress towards protecting at least 10% of the global ocean by 2020. It is estimated that > 6,000 marine protected areas, covering c. 3.27% (12 million km2) of the oceans, had been designated by the end of 2013. However, protection is generally weak, with c. one-sixth (1.9 million km2) of the combined area designated as no-take areas (i.e. fishing and other extractive activities are prohibited). Additional large tracts of ocean will need to be protected to reach the 10% target, and we investigate hypothetical scenarios for such expansion. Such scenarios offer a one-dimensional measure of progress as they do not address aspects of other global targets, such as Aichi Target 11, which will help to ensure that marine protected areas meet their objectives and achieve conservation outcomes.