Large Marine Mammals Research Articles

Bioadhesive interface for marine sensors on diverse soft fragile species

Marine animals equipped with sensors provide vital information for understanding their ecophysiology and collect oceanographic data on climate change and for resource management. Existing methods for attaching sensors to marine animals mostly rely on invasive physical anchors, suction cups, and rigid glues. These methods can suffer from limitations, particularly for adhering to soft fragile marine species such as squid and jellyfish, including slow complex operations, unreliable fixation, tissue trauma, and behavior changes of the animals. However, soft fragile marine species constitute a significant portion of ocean biomass (>38.3 teragrams of carbon) and global commercial fisheries. Here we introduce a soft hydrogel-based bioadhesive interface for marine sensors that can provide rapid (time <22 s), robust (interfacial toughness >160 J m−2), and non-invasive adhesion on various marine animals. Reliable and rapid adhesion enables large-scale, multi-animal sensor deployments to study biomechanics, collective behaviors, interspecific interactions, and concurrent multi-species activity. These findings provide a promising method to expand a burgeoning research field of marine bio-sensing from large marine mammals and fishes to small, soft, and fragile marine animals.

C and N stable isotopes enlighten the trophic behaviour of the dugong (Dugong dugon)

The dugong (Dugong dugon), a large marine mammal herbivore of the Indo-Pacific, is vulnerable to extinction at a global scale due to a combination of human-related threats including habitat degradation. The species forages on seagrass habitats (marine phanerogams) and plays a key role in the functioning and sensitivity of these declining coastal ecosystems. The trophic behaviour and plasticity of dugong populations in response to extrinsic and intrinsic factors are therefore crucial features to both dugong and seagrass conservation. Yet, this knowledge remains limited to few visual observations and analyses of mouth, stomach or faecal contents of stranded individuals. We take advantage of a long-term monitoring of stranded individuals from the endangered New Caledonian population to depict features of dugongs’ trophic ecology from Carbon and Nitrogen stable isotopes. A total of 59 dugong skin samples were used to portrait the stable isotope niche of dugongs according to their sex and maturity. In light of previous work conducted in New Caledonia, a subset of these samples was used to model the trophic mix of dugong males and females. Our stable isotope mixing models used C and N isotope values of 10 taxa bbelonging to five divisions of metazoans, plants, and chromists. Our results represent the first estimate of the species dietary niche in the isotopic space. They suggest that the diet of dugong calves overlaps more with that of adult females (δ13C: − 6.38 ± 1.13 ‰; δ15N: 2.49 ± 1.10 ‰) than males (δ13C: − 5.92 ± 1.10 ‰; δ15N: 3.69 ± 1.28 ‰). Further, we highlight differences in the expected trophic mix of dugong adult males and females. From these, we formulate a sex-specific foraging behaviour hypothesis in dugongs, whereby lactating females could forage over smaller spatial ranges but more diverse food sources thanmales. The study emphasizes the importance of long-term stranding monitoring programs to study the ecology of marine mammals.. Finally, it depicts an ecological feature that may contribute to the sensitivity of vulnerable dugongs to ongoing changes on tropical coastal ecosystems.

Where are the whales? Continued acoustic monitoring efforts of California’s Central Coast

Understanding and conserving ocean ecosystems is a difficult, but important task made easier with bioacoustic technology. Although marine mammal monitoring efforts can be done with visual surveys, they often lack temporal information on a finer scale. Long-term passive acoustic monitoring efforts of critical migratory species can provide detailed information about the region’s marine soundscape that is key to conservation efforts. The aim of our project is to establish a long-term bioacoustic monitoring station off the coast of central California and help close the gap in our understanding of marine mammal presence along the Pacific coastline. The goals put forth by the bioacoustic lab for this academic year include (1) determining probable species presence, (2) ascertaining temporal (day/night) variations of vocalizations, and (3) examining key differences in species and call type between two deployments from Fall 2022 and Winter 2023. These comparisons will be crucial to help develop a baseline understanding of seasonal and temporal variations of the soundscape in our region. We aim to implement various long-term deployments in order to gather more complete and consistent bioacoustic data in our local waters. These deployments and the subsequent analysis will contribute to large scale marine mammal monitoring and conservation efforts. [This project was made possible by a grant from the Santa Rosa Creek Foundation and the COAST undergraduate research fund.]

Marine Conservation Analysis Of Dugong Life Habitat Ecosystem

The dugong (Dugong dugon) is a large marine mammal belonging to the order Sirenia and is one of four living species of sea cows, along with the manatees. Dugongs are found throughout the Indo-Pacific region, inhabiting shallow coastal waters, estuaries, lagoons, and seagrass beds, making them highly dependent on seagrass ecosystems for their survival. The dugong is classified as vulnerable to extinction by the International Union for Conservation of Nature (IUCN), with population declines attributed to habitat loss, hunting, accidental capture, and climate change. Therefore, conservation efforts are essential to ensure the survival of the dugong and the maintenance of the ecological services provided by seagrass ecosystems. The current state of knowledge on dugongs and their conservation can be synthesized based on the findings of the ten selected references. Overall, these references provide evidence for the importance of seagrass meadows as habitat and food source for dugongs, as well as for the numerous threats facing this species. Overall, the reviewed literature underscores the importance of engaging local com-munities in dugong conservation efforts. Community-based conservation interventions have the potential to reduce hunting pressure on dugongs and promote positive attitudes towards conservation. Furthermore, the recognition of the cultural significance of dugongs can foster greater community involvement and support for conservation initiatives.

Long‐term persistence of large dugong groups in a conservation hotspot around Hawar Island, Kingdom of Bahrain

Abstract Predictable aggregations of large marine mammals are valuable conservation targets, but aggregated populations can also be exposed to site‐level threats. The globally vulnerable Dugong dugon has a wide distribution but is found in large numbers mainly in Australia and the Arabian Gulf. Though Australian dugong populations are well studied, much less is known of the dugongs in the Arabian Gulf. The spatial and temporal persistence of dugongs around Bahrain, with a focus on large dugong groups (&gt;50 dugongs), was determined using an occupancy modelling framework supported by historical records, structured interviews, citizen science network reports, and small‐scale boat and unmanned aerial vehicle surveys. Historical records and current distributional studies confirmed that large dugong groups have been reliably sighted around Hawar Island (Bahrain) since at least 1986, forming large, clumped groups that persist almost year round. The largest recorded so far in the world, these fluid groups (maximum of ~700 dugongs) account for ~60% of the dugongs found in Bahrain and ~12% of all dugongs in the Arabian Gulf. The delineated occupancy core area of large dugong groups (~145 km2) straddles the Bahrain–Qatar border, reflecting the transboundary nature of these groups. Careful management of human‐induced stressors (in particular, fishing, boating, and coastal development) combined with regular monitoring of Hawar Island's large dugong groups and their seagrass habitat is critical to safeguard this globally important population. The effectiveness of any conservation management is predicated on strengthening cooperation among all range states in the Arabian Gulf. A key recommendation of this study is to establish a regional network of marine protected areas encompassing core aggregation sites for dugongs, particularly the Hawar Islands in Bahrain, the north‐western waters of Qatar, Marawah Island in the United Arab Emirates in addition to the shallow waters between Saudi Arabia, Qatar, and United Arab Emirates.

Herd Size Dynamics and Observations on the Natural History of Dugongs (Dugong dugon) in the Andaman Islands, India

In the last four decades, dugong (Dugong dugon) aggregations have been rarely reported from the geographically isolated, vast seascape of the Andaman Islands, India. The Indian Ocean tsunami of 2004, hunting, coastal development, and habitat loss are the major causes of this change in the social system of dugongs in the Andaman Islands. Our long-term monitoring study (2017 to 2022) reveals a changing trend in aggregating behaviour of dugongs. In an inclusive, collaborative effort, we engaged multiple stakeholders using two approaches: (1) creating a spatially spread citizen science network targeting sea-faring agencies—the fishers, forest department, SCUBA divers, and defence bodies (Indian Navy and Indian Coast Guard); and (2) conducting standardized questionnaire surveys (UNEP/CMS) with fishers. Our approach yielded reports of 63 herd sightings of dugongs from the Andaman archipelago. The fishers reported 73.01% of the sightings, followed by the defence bodies (20.63%), forest department (3.18%), and SCUBA divers (3.18%). Smaller herds in our study comprised three to six individuals, with a social structure of “adults only” and “adult–calf.” The larger herds of seven to 13 individuals included an “adult–calf” combination with a greater number of adults accompanying two to three calves. More than 95% of these herd occurrences were reported from sheltered, coastal waters with resource concentrations (large seagrass meadows). Further, we present novel dugong occurrence reports from data-deficient regions like the Jarawa Tribal Reserve and the North Sentinel Island, along with dugong occurrences from Little Andaman, where the population was speculated to be locally extinct after the 2004 tsunami. These findings strongly advocate the involvement of multiple stakeholders as a cost-effective approach to monitoring the distribution and population of dugongs in larger seascapes like the Andaman and Nicobar Islands. Moreover, such an approach would be critical for sensitizing the local stakeholders regarding the conservation and management of large marine mammals such as dugongs.

An Inventory of Some Relatively Large Marine Mammals, Reptiles, and Fishes Sighted, Caught, By-Caught, or Stranded in the Mediterranean Coast of the Gaza Strip-Palestine

The Mediterranean Sea is home to an interesting biodiversity. The current cumulative and descriptive study aims to enumerate some relatively large marine mammals, reptiles, and fishes that have been spotted, caught, by-caught, or stranded on the coast of the Gaza Strip, Palestine, which extends about 42 km along the Mediterranean Sea. This 20-year study from 2003 to 2022 relied much on frequent field visits, meetings, and discussions with stakeholders, following local media sites and social media pages, and photography. The study recorded at least 26 giants or relatively large marine organisms on the Mediterranean coast of the Gaza Strip, Palestine. Certainly, the coming years may bring other marine organisms of relatively large sizes. Marine mammals included three species of cetaceans with the Fin Whale (Balaenoptera physalus) being the largest mammal and even the largest animal ever recorded in this study. Marine reptiles included three species of sea turtles, the largest of which is the Leatherback Sea Turtle (Dermochelys coriacea), which is in fact the world’s largest sea turtle. The bony fishes were represented by ten species, the largest of which was the Ocean Sunfish (Mola mola), which is the largest bony fish in the world. The cartilaginous fishes included ten species with the largest specimens encountered were the Shortfin Shark (Isurus oxyrinchus), Bluntnose Sixgill Shark (Hexanchus griseus), Scalloped Hammerhead Shark (Sphyrna lewini), and Giant Devil Ray (Mobula mobular). Seabirds were not included in the study. The Alexandria Pompano (Alectis alexandrinus) and the Silver-Cheeked Toadfish (Lagocephalus sceleratus), which are bony fishes, appear to be the relatively smallest marine organisms recorded here. In conclusion, the role of the various parties must be coordinated to ensure the sustainability of human activities and their compatibility with the task of conserving local marine biota, including the gigantic or relatively large ones.

Shorebirds ingest plastics too: what we know, what we do not know, and what we should do next

Concerns about the impact of plastics pollution on the environment have been growing since the 1970s. Marine debris has reportedly entangled and (or) been ingested by 914 marine species ranging from microinvertebrates to large marine mammals. Shorebirds have a high potential to be exposed to and ingest plastics pollution, as many species migrate long distances and periodically concentrate around shorelines, coastal areas, and estuaries that can have elevated levels of plastics pollution. Currently, little is understood about plastics exposure, frequency of occurrence (FO), and potential impacts relating to shorebirds. In this study, we catalogued and reviewed available studies across the globe that examined plastics pollution in shorebirds. We then quantified relevant traits of species and their environments to explore how shorebirds may be exposed to plastics pollution. Of 1106 samples from 26 shorebird species described within 16 studies that examined plastic ingestion, 53% of individuals contained some form of plastics pollution. Overall, Haematopodidae (oystercatchers) had the highest FO of plastics, followed by Recurvirostridae (avocets), Scolopacidae (sandpipers, phalaropes, godwits, and curlews), and Charadriidae (plovers). Plastics FO was much greater among species that migrated across marine areas (either oceanic or coastal) than those species that used continental flyways. Species that foraged at sea, on mudflats, or on beaches had higher average FO of plastic ingestion than species that foraged in upland or freshwater environments. Finally, species that used a sweeping foraging mode showed higher levels of ingested plastics and contained a far greater number of plastic pieces than all other techniques. These conclusions are based on a limited number of species and samples, with the distribution of samples skewed taxonomically and geographically. Using the combined knowledge of known shorebirds–plastics interactions and shorebird ecology, we present a hierarchical approach to identifying shorebirds that may be more vulnerable and susceptible to plastic ingestion. We provide recommendations on sampling protocols and future areas of research.

Slicing the pie: Interpreting harmful algal blooms one pie chart at a time

The Earth’s oceans are home to a diverse array of life, from large marine mammals to microscopic organisms. Among the most important are the marine phytoplankton, which comprise the basis of marine food webs, and also produce a large percentage of the Earth’s oxygen through photosynthesis. Although the vast majority of phytoplankton are essential to ocean health, several dozen species produce potent toxins, and can form what are called Harmful Algal Blooms (HABs). This science activity focuses on the importance of HABs, as well as the types of data scientists collect to understand blooms. In the classroom exercises, students will calculate the proportional abundance (% contribution) of five HAB species present in water samples, and use these data to create pie graphs to depict species composition. Students will then compare these results with levels of HAB toxins in water samples collected over the same time period. Thought questions challenge students to develop hypotheses regarding how changes in the HAB community may relate to observed trends in toxin concentrations. This activity was successfully taught to visually impaired students who were able to complete the pie charts and answer the thought questions.

Blue Whale Body Condition Assessed Over a 14-Year Period in the NE Pacific: Annual Variation and Connection to Measures of Ocean Productivity

Large marine mammals can serve as an indicator of the overall state of the environment due to their apex position in marine food webs and their functions as sentinels of change. Reductions in prey, driven by changes in environmental conditions can manifest in reduced fat stores that are visible on whales. We developed a non-invasive technique using photographs of blue whales taken on the US west coast from 2005-2018 (n=3,660) and scored body condition based on visible undulations from the vertebral processes and body shape. We analyzed patterns in the body condition of whales across years and their relation to oceanographic conditions. Females with calves had significantly poorer body conditions and calves had significantly better body conditions compared to other adult whales (Chi-Square, x2 = 170.36, df=6, p&amp;lt;2.2e-16). Year was a significant factor in body condition (Chi-Square, x2 = 417.73, df=39, p&amp;lt;0.001). The highest proportion of whales in poor body condition was observed for 2015 (one of the only two years along with 2017 where &amp;gt;50% had poor body condition) coincides with the marine heat wave that affected the NE Pacific 2014-2016. A cumulative mixed model examining the relationship between body condition and environmental variables revealed that negative Pacific Decadal Oscillation and longer upwelling seasons correlated with better blue whale body condition, likely to be due to higher primary productivity and prey availability. This study indicates that with an adequate scoring method, photographs collected during boat based surveys can be used to effectively evaluate whale health in response to a changing ocean.

Morphometric study of humpback whale mother-calf pairs in the Sainte Marie channel, Madagascar, using a simple drone-based photogrammetric method

Morphometric studies of humpback whales (Megaptera novaeangliae) occurring in the Indian Ocean area have been limited by the technology currently available. In the Sainte Marie channel, Madagascar, straightforward aerial single-camera photogrammetry was tested on mother-calf pairs that combines standard Unoccupied Aerial Vehicle (UAV) with free, easy-to-access, and user-friendly software. The goals of the study were to estimate mother and calf body measurements and to investigate the effect of maternal parity (primiparous versus multiparous, based on length) on calf size. A mean length of 12.4±1.2 m for mothers (N = 16) and 5±0.9 m for calves (N = 16) was estimated. The size of calves did not depend significantly on maternal parity. The photogrammetry method used was simple and cost-effective, yet produced convincing morphometric measurements with acceptable precision and accuracy. The coefficients of variation (CVs) of repeated estimates and the level of error were relatively low (CV = 2.31 % for a known-sized object and average CV = 2.52 % for individual whales; average error = 1.8 % for a known-sized object). These results will encourage more teams to study the morphometry of large marine mammals despite limitations in terms of resources.

Los mamíferos marinos, buzos por naturaleza.

Marine mammals are a diverse group, including 130 species. These animals have acquired, through evolution, traits that allow them to live at sea. One of the most striking features of marine mammals is that, although they have lungs, they can dive to great depths while holding their breath for extended periods. Diving allows them to meet basic needs such as feeding, mating, and can provide protection from predators. The duration and depth of the dives is associated to physiological adaptations, including increased hemoglobin and myoglobin reserves, and antioxidant defenses, that can be influenced by the size of each species. For example, sea otters can reach depths of less than 20 m, while larger marine mammals such as the sperm whale can descend up to 3000 m. This paper presents the general characteristics of marine mammals and briefly describes the morphological and physiological adaptations that allow them to dive without suffering the consequences of oxidative stress.

Plastic pollution: why is it a public health problem?

Plastic pollution: why is it a public health problem?

Plastination of a sperm whale.

In 2016, two adult male sperm whales beached off of Yangkou Port in Nantong City, Jiangsu Province, China. The local government planned to preserve them as specimens, one was entrusted to Dalian Hoffen Biological Co., Ltd., and thus became the first sperm whale to be preserved by plastination. The other sperm whale was preserved in Nantong by the traditional stripping method (The skin was preserved, and then the prosthesis was filled into the skin to preserve the specimens. The material of the prosthesis was polyurethane. The outline of the animal was sculpted by suturing the skin like a bag and filling it with polyurethane). Plastination of such a large marine mammal allowed us to view the mutual adaptations of its internal structure to its specific living environment and daily habits. This sperm whale is the largest specimen in the world and this is the first time a sperm whale has been preserved using the plastination method. The plastination process also provides a method for studying the anatomy of large marine mammals for humans to understand deep-sea organisms at close contact and visual level. The plastination of this sperm whale promises to be a world class resource holding tremendous scientific, educational, and artistic value.

Synchrony erodes spatial portfolios of an anadromous fish and alters availability for resource users.

Environmental forces can create spatially synchronous dynamics among nearby populations. However, increased climate variability, driven by anthropogenic climate change, will likely enhance synchrony among spatially disparate populations. Population synchrony may lead to greater fluctuations in abundance, but the consequences of population synchrony across multiple scales of biological organization, including impacts to putative competitors, dependent predators or human communities, are rarely considered in this context. Chinook salmon Oncorhynchus tshawytscha stocks distribute across the Northeast Pacific, creating spatially variable portfolios that support large ocean fisheries and marine mammal predators, such as killer whales Orcinus orca. We rely on a multi-population model that simulates Chinook salmon ocean distribution and abundance to understand spatial portfolios, or variability in abundance within and among ocean distribution regions, of Chinook salmon stocks across 17 ocean regions from Southeast Alaska to California. We found the expected positive correlation between the number of stocks in an ocean region and spatial portfolio strength; however, increased demographic synchrony eroded Chinook salmon spatial portfolios in the ocean. Moreover, we observed decreased resource availability within ocean fishery management jurisdictions but not within killer whale summer habitat. We found a strong portfolio effect across both Southern Resident and Northern Resident killer whale habitats that was relatively unaffected by increased demographic synchrony, likely a result of the large spatial area included in these habitats. However, within the areas of smaller fishing management jurisdictions we found a weakening of Chinook salmon portfolios and increased but inconsistent likelihood of low abundance years as demographic synchrony increased. We suggest that management and conservation actions that reduce spatial synchrony can enhance short-term ecosystem resilience by promoting the stabilizing effect multiple stocks have on aggregate Chinook salmon populations and overall resource availability.

Detection of the elusive Dwarf sperm whale (Kogia sima) using environmental DNA at Malpelo island (Eastern Pacific, Colombia).

Monitoring large marine mammals is challenging due to their low abundances in general, an ability to move over large distances and wide geographical range sizes.The distribution of the pygmy (Kogia breviceps) and dwarf (Kogia sima) sperm whales is informed by relatively rare sightings, which does not permit accurate estimates of their distribution ranges. Hence, their conservation status has long remained Data Deficient (DD) in the Red list of the International Union for Conservation of Nature (IUCN), which prevent appropriate conservation measures.Environmental DNA (eDNA) metabarcoding uses DNA traces left by organisms in their environments to detect the presence of targeted taxon, and is here proved to be useful to increase our knowledge on the distribution of rare but emblematic megafauna.Retrieving eDNA from filtered surface water provides the first detection of the Dwarf sperm whale (Kogia sima) around the remote Malpelo island (Colombia).Environmental DNA collected during oceanic missions can generate better knowledge on rare but emblematic animals even in regions that are generally well sampled for other taxa.

Intrigue surrounding the life-cycles of species of Clistobothrium (Cestoda: Phyllobothriidea) parasitising large pelagic sharks

This study aimed to locate the adults, and thus also the definitive hosts, of three species of marine mammal-parasitising larval cestodes that have molecular affinities with Clistobothrium. New collections led to the discovery of adults of two new species of Clistobothrium, one from the longfin mako shark and one from the salmon shark. New material of Clistobothrium tumidum was collected from the great white shark and new material of a previously reported undescribed species of Clistobothrium was collected from the porbeagle shark. Larvae of Clistobothrium were opportunistically collected from sockeye salmon and four species of small squaliform sharks. Sequence data for the D1–D3 region of the 28S rDNA gene were generated for all but one of these taxa. The tree resulting from maximum likelihood analysis of those data, in combination with comparable data from GenBank, indicates that squaliform sharks can serve as intermediate hosts for the species from the porbeagle shark. The larvae from salmon exhibit a unique molecular signature and, based on diet data, may be conspecific with adults from the salmon shark. Informed by sequence data for new material of Monorygma and existing data for Phyllobothrium, the larvae provisionally identified as Monorygma grimaldii and Phyllobothrium delphini were formally transferred to Clistobothrium. Especially puzzling was that the molecular signatures of none of the eight species of Clistobothrium match those of the three marine mammal-parasitising larval forms. We are at a loss as to where else to look for the three corresponding adult forms. The great white shark remains the most likely candidate given it consumes marine mammals with some regularity, but seems unlikely to host five species of Clistobothrium. Alternatively, we are left wondering if the large marine mammal predator Carcharocles megalodon may not be extinct after all.

Applying Two Active Acoustic Technologies to Document Presence of Large Marine Animal Targets at a Marine Renewable Energy Site

Coastal regions are highly used by humans. The growing marine renewable energy (MRE) industry will add to existing anthropogenic pressures in these regions. Regulatory bodies require animal risk assessment before new industrial activities can progress, and MRE is no exception. Preliminary data of marine mammal use of an MRE device deployment location could be informative to permitting. A combination of downlooking hydroacoustics using an echosounder and acoustic camera (imaging sonar) was used to provide a number of large targets (proxy for large fish and marine mammals) in an area of interest for MRE tidal turbine deployment in Western Passage, Maine, USA. Data were collected in May, June, August, and September of 2010 and 2011. Of the nine large targets confirmed to be animals, eight were porpoises and one was a shark. Few large targets were observed in May and June, with the majority (90%) being present in August and September of both years. The most large targets were observed when tidal current speed was less than 1 m·s−1. These data provide a preliminary assessment of large targets in a single location over sixteen 24-h surveys. The aforementioned methodology could be used for future pre- and post-installation assessments at MRE device deployment locations. Their use in concert with visual and passive acoustic monitoring can provide water depth usage by marine mammals, which is a metric that is difficult to assess with passive acoustic and visual techniques.

Animal Welfare in Predator Control: Lessons from Land and Sea. How the Management of Terrestrial and Marine Mammals Impacts Wild Animal Welfare in Human-Wildlife Conflict Scenarios in Europe.

Simple SummaryBoth marine and terrestrial mammal predators come into conflict with humans in Europe and yet their situations are rarely compared. Areas of conflict include the predation of livestock and farmed fish, and also perceived competition for wild prey (for example wolves competing with hunters for deer and seals competing with fishermen for salmon). A lethal method (shooting) and non-lethal methods of conflict reduction used for terrestrial large carnivores (e.g., bear, wolf, wolverine, lynx) and marine mammals (seals) are discussed and their potential impacts on predator welfare are considered. The importance of carrying out an animal welfare assessment when choosing a control method is emphasized along with possible assessment methods. Recommendations for future work are also made.The control of predators, on land and in the sea, is a complex topic. Both marine and terrestrial mammal predators come into conflict with humans in Europe in many ways and yet their situations are rarely compared. Areas of conflict include the predation of livestock and farmed fish, and the perceived competition for wild prey (for example wolves competing with hunters for deer and seals competing with fishermen for salmon). A lethal method (shooting) and non-lethal methods of conflict reduction (including enclosures, guarding, and aversion) used for terrestrial large carnivores (e.g., bear, wolf, wolverine, lynx) and marine mammals (seals) are discussed. Control measures tend to be species- and habitat-specific, although shooting is a widely used method. Potential impacts on predator welfare are described and welfare assessments which have been developed for other wildlife control scenarios, e.g., control of introduced species, are considered for their potential use in assessing predator control. Such assessments should be applied before control methods are chosen so that decisions prioritizing animal welfare can be made. Further work needs to be carried out to achieve appropriate and widely-accepted animal welfare assessment approaches and these should be included in predator management planning. Future research should include further sharing of approaches and information between terrestrial and marine specialists to help ensure that animal welfare is prioritized.

Invited Lecture 2: Endocrine disrupting chemicals in ocean ecosystem and human health risks

Brief Biosketch He is the author of 5 books and edited 7 books (chapters). He has published peer-reviewed articles in several reputed journals. He is serving as a Course Coordinator for Undergraduate (MD) teaching: Environmental health. There are 2 notified research grants in his credit: CIHR Project Grant (Spring 2019) and NSERC along with 3 ongoing projects. He was awarded Faculty of Medicine, Memorial University Outstanding Research Excellence Award (2015) and SSHRC Travel Grants Competition, Annual conference of International Society of Environmental Epidemiology, Basel, Switzerland (2013). His area of research interest is Environmental contamination and ecosystem health, Climate change and health, Indigenous health, Global Health and Social epidemiology. Endocrine disrupting chemicals (EDCs) are the exogenous substances that can cause adverse health effects through disruption to the body's endocrine systems. This can result in changes to circulating hormone concentrations, which act as signals to regulate growth, metabolism and reproduction. Hormones are maintained at very low concentrations in the bloodstream; therefore, even low levels of EDC exposure can have large consequences on endocrine homeostasis. The potential adverse health effects resulting from exposure to EDCs, including developmental abnormalities, abnormal hormonal profiles, disorders of the reproductive systems, increased incidence of cancer, and alterations to both the immune and nervous systems. There are numerous chemicals used in our day to day basis have endocrine disruption property, such as pesticides, flame retardants, and various other industrial chemicals. Humans are exposed to those chemicals from direct exposures while using them, and also from the diet. EDCs reach environment from deposition via industrial effluents or direct application and also through wastewater and landfills. Eventually, these chemicals destine to aquatic ecosystems, such as rivers, ponds, lakes, seas and oceans. Humans further get exposed to EDCs by eating marine products. The bio-accumulative and bio-magnification nature of EDCs result in their very high levels in large predatory fish and marine mammals. Studies show the people who regularly eat marine products contaminated with EDCs encounter various forms of adverse health outcomes such as thyroid hormone disruptions, infertility, and other endocrine diseases. Despite extensive literature available in industrialized countries, studies conducted in resource constraint countries are very few. Therefore, more research needed to generate further evidence.