The magnitude and sustainability of marine mammal by-catch in fisheries in East Malaysia

The magnitude and sustainability of incidental catches of marine mammals in fisheries was investigated in Sabah and Sarawak, East Malaysia, using a combination of interview surveys and observer trips on fishing boats. These fisheries involve around 15,000 registered fishing boats and generate annual landings of around 350,000 tonnes. Between March 1997 and December 2004, we interviewed fishermen working on 753 and 358 boats in Sabah and Sarawak, respectively, who were employing trawl nets, purse seines, gillnets and fish stakes. They were asked questions about sightings of marine mammals and interactions with fishing. We also followed 36 trawl and 10 purse seine fishing trips in Sabah between June 2003 and December 2004. Fishing was conducted in coastal waters and total annual catches by each method and region were estimated. Incidental catches of marine mammals were reported by fishermen from 310 (41%) and 99 (28%) fishing boats in Sabah and Sarawak, respectively. Gill-netters, trawlers and fish stakes were reported to catch cetaceans and dugongs, while purse seiners caught only cetaceans. The Irrawaddy dolphin, bottlenose dolphin, spinner dolphin, pantropical spotted dolphin, Indo-Pacific humpback dolphin and finless porpoise are the cetacean species known to be taken. Overall, the magnitude of incidental catches of marine mammals is greatest in gillnets. No marine mammal catches were seen during observer trips. Interview results suggest annual by-catches of 306 (95% CI = 250–369) cetaceans and 479 (95% CI = 434–528) dugongs in Sabah. Estimates for Sarawak were 221 (95% CI = 189–258) cetaceans per year and 14 (95% CI = 2–30) dugongs. These results suggest that by-catch rates, particularly in gillnets, may be unsustainably high. A dedicated monitoring and educational programme, together with the establishment of Marine Protected Areas, is urgently needed to minimize the threat.

Download Full-text

Recommendations for Sustainable Cetacean-Based Tourism in French Territories: A Review on the Industry and Current Management Actions

Tourism in Marine Environments ◽

10.3727/154427320x15943351217984 ◽

2020 ◽

Vol 15 (3) ◽

pp. 211-235

Author(s):

Josephine Chazot ◽

Ludovic Hoarau ◽

Pamela Carzon ◽

Jeanne Wagner ◽

Stéphanie Sorby ◽

...

Keyword(s):

Marine Mammal ◽

Marine Mammals ◽

French Polynesia ◽

Legal Framework ◽

Whale Watching ◽

Cetacean Species ◽

Commercial Activities ◽

Management Actions ◽

Overseas Territories ◽

Socioeconomic Benefits

Whale-watching activities provide important socioeconomic benefits for local communities and constitute powerful platform incentives for marine mammals' protection or more broadly marine environments. However, these activities can cause adverse effects on targeted populations, with considerable downside associated risks of injuries and fatality for whale watchers during inwater interactions. France with its overseas territories has the second largest exclusive economic zone (EEZ), in which more than half of existing cetacean species are encountered. In these territories, recreational and commercial whale watching, including swim-with cetacean activities, have recently developed. Yet few studies focused on these activities and their associated impacts across French territories, leading to an unclear assessment of the situation. To address this issue, we reviewed cetaceans' occurrence within the French EEZ, whale-watching industry, targeted species, local management of marine mammal-based tourism activities, and regulations in France mainland and some overseas territories (Reunion Island, Mayotte, and French Polynesia). Fortyeight species are encountered in the French EEZ, and 15 are targeted by whale-watching activities. A total of 185 operators, including 34% offering swim-with-cetaceans tours, offered trips in France and overseas in 2019. While several more or less restrictive regulations exist locally, our results indicate that French's national legal framework for marine mammals' protection remains inadequate and insufficient to cope with the recent development of this activity. As conservation biologists, managers, and stakeholders from these French territories, we cooperated to provide general guidelines for a sustainable development of whale watching at a national scale. We urge (1) to legally acknowledge and regulate whale-watching commercial activities; (2) to create a national legal framework regarding whale watching and swim-with marine mammals practices, while accounting for local distinctiveness and disparities across regions; (3) to conduct more research to evaluate local short- and long-term impacts on targeted marine mammal populations as well as the socioeconomic benefits; and (4) to reinforce synergetic relations between the different stakeholders.

Download Full-text

A review of marine mammal records of Cuba

Latin American Journal of Aquatic Mammals ◽

10.5597/lajam00175 ◽

2014 ◽

Vol 9 (2) ◽

pp. 65-122 ◽

Cited By ~ 1

Author(s):

Amy Danae Whitt ◽

Thomas A. Jefferson ◽

Miriam Blanco ◽

Dagmar Fertl ◽

Deanna Rees

Keyword(s):

Marine Mammal ◽

Marine Mammals ◽

Cetacean Species ◽

Baleen Whales ◽

Common Bottlenose Dolphin ◽

Extant Species ◽

Pinniped Species ◽

The Common ◽

The Caribbean ◽

West Indian Manatee

There has been very little research on marine mammals in Cuban waters. Much of the information on marine mammals in this region is buried in historical and gray literature. In order to provide a comprehensive account of marine mammal occurrence in Cuba’s Exclusive Economic Zone (EEZ), we reviewed and verified 659 published and unpublished sighting, stranding, capture, and tagging records. Eighteen extant species and four genera have confirmed records for Cuban EEZ waters. This includes 17 species of cetaceans (three baleen whales and 14 toothed whales) and one sirenian species. An additional 11 cetacean species and one extant pinniped species have been reported, but not confirmed, or may have the potential to occur in Cuban waters. Historical records of the Caribbean monk seal (Monachus tropicalis) are documented in Cuba; however, this species is now considered extinct. The only two species that are seen regularly and considered common in Cuban nearshore waters are the common bottlenose dolphin (Tursiops truncatus) and the West Indian manatee (Trichechus manatus).

Download Full-text

SARS-CoV2, A Threat to Marine Mammals? A Study From Italian Seawaters

10.21203/rs.3.rs-378165/v1 ◽

2021 ◽

Author(s):

Tania Audino ◽

Carla Grattarola ◽

Cinzia Centelleghe° ◽

Simone Peletto ◽

Federica Giorda ◽

...

Keyword(s):

Marine Mammal ◽

Marine Mammals ◽

Disease Outbreaks ◽

Population Data ◽

Global Scale ◽

Extreme Weather Events ◽

Health Economy ◽

Wastewater Management ◽

Potential Hazard ◽

Cetacean Species

Abstract Zoonotically transmitted coronaviruses were responsible for three disease outbreaks since 2002, with the “Severe Acute Respiratory Syndrome Coronavirus-2” (SARS-CoV-2) causing the dramatic “Coronavirus Disease-2019” (CoViD-19) pandemic, which affected public health, economy, and society on a global scale. The impacts of the SARS-CoV-2 pandemic permeate into our environment and wildlife as well; in particular, concern has been raised about the viral occurrence and persistence in aquatic and marine ecosystems. The discharge of untreated wastewaters carrying infectious SARS-CoV-2 into natural water systems that are home of sea mammals may have dramatic consequences on vulnerable species. The efficient transmission of coronaviruses raises questions regarding the contributions of virus-receptors interactions. The main receptor of SARS-CoV-2 is Angiotensin Converting Enzyme-2 (ACE-2), serving as a functional receptor for the viral spike (S) protein. This study was aimed, through the comparative analysis of the ACE-2 receptor with the human one, at assessing the susceptibility to SARS-CoV-2 of the different species of marine mammals living in Italian waters. We also determined, by means of immunohistochemistry, ACE-2 receptor localization in the lung tissue from different cetacean species, in order to provide a preliminary characterization of ACE-.2 expression in the marine mammals’ respiratory tract. Furthermore, in order to evaluate if and how wastewater management in Italy may lead to susceptible marine mammal populations being exposed to the virus, geo-mapping data of wastewater plants, associated to the identification of specific stretches of coast more exposed to extreme weather events, overlapped to marine mammal population data, were carried out. Results showed the SARS-CoV-2 exposure for marine mammals inhabiting Italian coastal waters. Thus, we highlight the potential hazard of reverse zoonotic transmission of SARS-CoV-2 infection, along with its impact on marine mammals regularly inhabiting the Mediterranean Sea, whilst also stressing the need of appropriate action to prevent further damage to specific vulnerable populations.

Download Full-text

Marine mammals used as bait for improvised fish aggregating devices in marine waters of Ecuador, eastern tropical Pacific

Endangered Species Research ◽

10.3354/esr01015 ◽

2020 ◽

Vol 41 ◽

pp. 289-302 ◽

Cited By ~ 3

Author(s):

C Castro ◽

K Van Waerebeek ◽

D Cárdenas ◽

JJ Alava

Keyword(s):

Marine Mammal ◽

Marine Mammals ◽

Tropical Pacific ◽

South American ◽

Physeter Macrocephalus ◽

Eastern Tropical Pacific ◽

Cetacean Species ◽

Pilot Whale ◽

Sea Lions ◽

Fish Aggregating Devices

Fish aggregating devices (FADs) are floating objects typically used to attract and capture pelagic fish in industrial tuna fisheries. This study documents 9 cases, involving 31 marine mammals, of incidentally captured, killed or otherwise retrieved cetaceans and pinnipeds which were used, or presumably used, as bait for improvised fish aggregation devices (IFAD) by artisanal fishers in coastal Ecuador. At least 3 species of small cetaceans were affected, including pantropical spotted dolphin Stenella attenuata, short-finned pilot whale Globicephala macrorhynchus, pygmy killer whale Feresa attenuata and an unidentified small delphinid, as well as South American sea lions Otaria byronia which were reportedly killed on purpose for this fishing practice. A sperm whale Physeter macrocephalus and a humpback whale Megaptera novaeangliae were presumably found floating at sea and opportunistically exploited as FADs. The South American sea lion represented 80.6% of marine mammals used as bait associated with FADs (25 sea lions out of 31 marine mammals), while the remaining 5 (possibly 6) cetacean species represented 19.4%. This is the first report of baited FADs in Ecuador, the extent of which is still unknown. This fishing technique has not been documented in other nations along the west coast of South America, although baiting of gillnets with marine mammal parts is common in Peru. Without fisheries management and regulation, this illegal fishing practice could rapidly expand and lead to further direct kills and conservation problems for targeted marine mammal populations in the eastern tropical Pacific. A bottom-up fisheries policy in concert with community-based conservation to ban the use of marine mammals as FAD bait is recommended.

Download Full-text

SARS-CoV2, a threat to marine mammals? A study from Italian seawaters

10.1101/2021.03.29.437540 ◽

2021 ◽

Author(s):

Tania Audino ◽

Carla Grattarola ◽

Cinzia Centelleghe ◽

Simone Peletto ◽

Federica Giorda ◽

...

Keyword(s):

Marine Mammal ◽

Marine Mammals ◽

Global Scale ◽

Extreme Weather Events ◽

Health Economy ◽

Wastewater Management ◽

Potential Hazard ◽

Mammal Species ◽

Cetacean Species ◽

Animal Reservoir

AbstractZoonotically transmitted coronaviruses were responsible for three disease outbreaks since 2002, with the “Severe Acute Respiratory Syndrome Coronavirus-2” (SARS-CoV-2) causing the dramatic “Coronavirus Disease-2019” (CoViD-19) pandemic, which affected public health, economy, and society on a global scale. The impacts of the SARS-CoV-2 pandemic permeate into our environment and wildlife as well; in particular, concern has been raised about the viral occurrence and persistence in aquatic and marine ecosystems. The discharge of untreated wastewaters carrying infectious SARS-CoV-2 into natural water systems that are home of sea mammals may have dramatic consequences on vulnerable species.The efficient transmission of coronaviruses raise questions regarding the contributions of virus-receptors interactions. The main receptor of SARS-CoV-2 is Angiotensin Converting Enzyme-2 (ACE-2), serving as a functional receptor for the viral spike (S) protein. This study was aimed, through the comparative analysis of the ACE-2 receptor with the human one, at assessing the susceptibility to SARS-CoV-2 of the different species of marine mammals living in Italian waters. We also determined, by means of immunohistochemistry, ACE-2 receptor localization in the lung tissue from different cetacean species, in order to provide a preliminary characterization of ACE-.2 expression in the marine mammals’ respiratory tract.Furthermore, in order to evaluate if and how wastewater management in Italy may lead to susceptible marine mammal populations being exposed to the virus, geo-mapping data of wastewater plants, associated to the identification of specific stretches of coast more exposed to extreme weather events, overlapped to marine mammal population data, were carried out. Results showed the SARS-CoV-2 exposure for marine mammals inhabiting Italian coastal waters. Thus, we highlight the potential hazard of reverse zoonotic transmission of SARS-CoV-2 infection, along with its impact on marine mammals regularly inhabiting the Mediterranean Sea, whilst also stressing the need of appropriate action to prevent further damage to specific vulnerable populations.Significance StatementGrowing concern exists that SARS-CoV-2, as already ascertained for its SARS-CoV and MERS-CoV “predecessors”, originated from an animal “reservoir”, performing thereafter its spillover into mankind, that was possibly anticipated by viral “passage” into a secondary animal host. Within the dramatic SARS-CoV-2 pandemic context, hitherto characterized by over 110 million cases and almost 2,500,000 deaths on a global scale, several domestic and wild animal species have been reported as susceptible to natural and/or experimental SARS-CoV-2 infection. In this respect, while some marine mammal species are deemed as potentially susceptible to SARS-CoV-2 infection on the basis of the sequence homology of their ACE-2 viral receptor with the human one, this study addresses such a critical issue also in stranded sea mammal specimens.

Download Full-text

SARS-CoV-2, a Threat to Marine Mammals? A Study from Italian Seawaters

Animals ◽

10.3390/ani11061663 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1663

Author(s):

Tania Audino ◽

Carla Grattarola ◽

Cinzia Centelleghe ◽

Simone Peletto ◽

Federica Giorda ◽

...

Keyword(s):

Marine Mammal ◽

Marine Mammals ◽

Global Scale ◽

Extreme Weather Events ◽

Wastewater Management ◽

Potential Hazard ◽

Cetacean Species ◽

Receptor Localization ◽

Sea Mammals ◽

The Impact

Zoonotically transmitted coronaviruses were responsible for Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), causing the dramatic Coronavirus Disease-2019 (CoViD-19) pandemic, which affected public health, the economy, and society on a global scale. The impact of the SARS-CoV-2 pandemic permeated into our environment and wildlife as well; in particular, concern has been raised about the viral occurrence and persistence in aquatic and marine ecosystems. The discharge of untreated wastewaters carrying infectious SARS-CoV-2 into natural water systems that are home to sea mammals may have dramatic consequences on vulnerable species. The efficient transmission of coronaviruses raises questions regarding the contributions of virus-receptor interactions. The main receptor of SARS-CoV-2 is Angiotensin Converting Enzyme-2 (ACE-2), serving as a functional receptor for the viral spike (S) protein. This study aimed, through the comparative analysis of the ACE-2 receptor with the human one, at assessing susceptibility to SARS-CoV-2 for different species of marine mammals living in Italian waters. We also determined, by means of immunohistochemistry, ACE-2 receptor localization in the lung tissue from different cetacean species, in order to provide a preliminary characterization of ACE-2 expression in the marine mammal respiratory tracts. Furthermore, to evaluate if and how Italian wastewater management and coastal exposition to extreme weather events may led to susceptible marine mammal populations being exposed to SARS-CoV-2, geomapping data were carried out and overlapped. The results showed the potential SARS-CoV-2 exposure for marine mammals inhabiting Italian coastal waters, putting them at risk when swimming and feeding in specific risk areas. Thus, we highlighted the potential hazard of the reverse zoonotic transmission of SARS-CoV-2 infection, along with its impact on marine mammals regularly inhabiting the Mediterranean Sea, while also stressing the need for appropriate action in order to prevent further damage to specific vulnerable populations.

Download Full-text

First record of Norwegian killer whales attacking and feeding on a harbour porpoise

Marine Biodiversity Records ◽

10.1017/s1755267215000895 ◽

2015 ◽

Vol 8 ◽

Cited By ~ 5

Author(s):

A. Mel Cosentino

Keyword(s):

North Atlantic ◽

Marine Mammals ◽

First Record ◽

Harbour Porpoise ◽

Sperm Whales ◽

Killer Whales ◽

Strait Of Gibraltar ◽

Cetacean Species ◽

The North ◽

Northern Bottlenose Whales

Orcinus orcais a cosmopolitan species and the most widely distributed marine mammal. Its diet includes over 140 species of fish, cephalopods, sea birds and marine mammals. However, many populations are specialised on certain specific prey items. Three genetically distinct populations have been described in the North Atlantic. Population A (that includes the Icelandic and Norwegian sub-populations) is believed to be piscivorous, as is population C, which includes fish-eating killer whales from the Strait of Gibraltar. In contrast, population B feeds on both fish and marine mammals. Norwegian killer whales follow the Norwegian spring spawning herring stock. The only description in the literature of Norwegian killer whales feeding on another cetacean species is a predation event on northern bottlenose whales in 1968. Daily land-based surveys targeting sperm whales were conducted from the Andenes lighthouse using BigEyes®binoculars (25×, 80 mm). The location of animals at sea was approximated through the use of an internal reticule system and a graduated wheel. On 24 June 2012 at 3:12 am, an opportunistic sighting of 11 killer whales was made off Andenes harbour. The whales hunted and fed on a harbour porpoise. Despite these species having overlapping distributions in Norwegian waters, this is the first predatory event reported in the literature.

Download Full-text

Fish and invertebrate by-catch in the crab pot fishery in the Isle of Man, Irish Sea

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315417001643 ◽

2017 ◽

Vol 98 (8) ◽

pp. 2099-2111

Author(s):

Fikret Öndes ◽

Michel J. Kaiser ◽

Lee G. Murray

Keyword(s):

Irish Sea ◽

Target Species ◽

Catch Per Unit Effort ◽

Isle Of Man ◽

Ecosystem Effects ◽

By Catch ◽

Catch Rates ◽

Taxonomic Groups ◽

Catch Composition ◽

Autumn And Winter

Baited trap or pot fisheries are considered to have relatively few wider ecosystem effects on the marine environment, particularly when compared with towed mobile fishing gear. However, this assumption is rarely tested in the field. This study aimed to determine the composition of non-target species that occur in crustacean pots and to assess spatial and temporal differences in catches in the waters around the Isle of Man, Irish Sea. The data were collected using fishery independent surveys and a questionnaire study. Based on fishery independent surveys, a total of five taxonomic groups and 43 species occurred as by-catch. The dominant by-catch species was velvet crab Necora puber. The by-catch per unit effort (BPUE) for all of the non-target species was low particularly in comparison to towed bottom gear fisheries around the Isle of Man. BPUE of species composition varied considerably between different locations around the Isle of Man. The results of both the fishery independent and questionnaire data suggested that the by-catch rates varied with season with peak BPUE occurring in spring which then declined into autumn and winter. By-catch composition did not decrease significantly with an increasing target species catch. Overall, by-catch was low relative to target species catch which may be partially attributable to the use of escape panels in pot fisheries in the Isle of Man.

Download Full-text

Schooling behaviour of jack mackerel, Trachurus declivis (Jenyns), observed in the Tasmanian purse seine fishery

Marine and Freshwater Research ◽

10.1071/mf9930577 ◽

1993 ◽

Vol 44 (4) ◽

pp. 577 ◽

Cited By ~ 10

Author(s):

H Williams ◽

G Pullen

Keyword(s):

School Size ◽

East Coast ◽

Diurnal Changes ◽

Jack Mackerel ◽

Schooling Behaviour ◽

Summer Schools ◽

By Catch ◽

Catch Rates ◽

Lunar Effects ◽

Purse Seine Fishery

The seasonal, lunar and diurnal changes in schooling of jack mackerel were examined using log-book information collected from an industrial fishery off the east coast of Tasmania between 1985 and 1989. School size increased significantly from spring to autumn. The ratio between surface and subsurface schools encountered by the fishery also changed seasonally. Surface schools predominate during summer, whereas subsurface schools become more frequent during autumn. The fishery was predominantly a day fishery and no lunar effects on catch rates or fishing intensity were detected. Catches mainly comprised jack mackerel, although redbait (Emmelichthys nitidus Richardson) and blue mackerel (Scomber australasicus Cuvier) were a significant by-catch. In summer, schools were almost exclusively composed of jack mackerel, but in other seasons mixed schools were found. Data presented, together with evidence from other sources, suggest that the availability of schools to the fishery may be closely related to the availability of feed.

Download Full-text

Cone visual pigments of aquatic mammals

Visual Neuroscience ◽

10.1017/s0952523805226159 ◽

2005 ◽

Vol 22 (6) ◽

pp. 873-879 ◽

Cited By ~ 54

Author(s):

LUCY A. NEWMAN ◽

PHYLLIS R. ROBINSON

Keyword(s):

Color Vision ◽

Mammalian Cells ◽

Marine Mammals ◽

Light Availability ◽

Splice Site Mutation ◽

Harbor Seal ◽

Site Mutation ◽

Cetacean Species ◽

Cone Opsin ◽

Aquatic Mammals

It has long been hypothesized that the visual systems of animals are evolutionarily adapted to their visual environment. The entrance many millions of years ago of mammals into the sea gave these new aquatic mammals completely novel visual surroundings with respect to light availability and predominant wavelengths. This study examines the cone opsins of marine mammals, hypothesizing, based on previous studies [Fasick et al. (1998) and Levenson & Dizon (2003)], that the deep-dwelling marine mammals would not have color vision because the pressure to maintain color vision in the dark monochromatic ocean environment has been relaxed. Short-wavelength-sensitive (SWS) and long-wavelength-sensitive (LWS) cone opsin genes from two orders (Cetacea and Sirenia) and an additional suborder (Pinnipedia) of aquatic mammals were amplified from genomic DNA (for SWS) and cDNA (for LWS) by PCR, cloned, and sequenced. All animals studied from the order Cetacea have SWS pseudogenes, whereas a representative from the order Sirenia has an intact SWS gene, for which the corresponding mRNA was found in the retina. One of the pinnipeds studied (harp seal) has an SWS pseudogene, while another species (harbor seal) appeared to have an intact SWS gene. However, no SWS cone opsin mRNA was found in the harbor seal retina, suggesting a promoter or splice site mutation preventing transcription of the gene. The LWS opsins from the different species were expressed in mammalian cells and reconstituted with the 11-cis-retinal chromophore in order to determine maximal absorption wavelengths (λmax) for each. The deeper dwelling Cetacean species had blue shifted λmax values compared to shallower-dwelling aquatic species. Taken together, these findings support the hypothesis that in the monochromatic oceanic habitat, the pressure to maintain color vision has been relaxed and mutations are retained in the SWS genes, resulting in pseudogenes. Additionally, LWS opsins are retained in the retina and, in deeper-dwelling animals, are blue shifted in λmax.

Download Full-text