Marine mammals

The populations of sharks worldwide are in sharp decline and therefore in urgent need of protection from illegal fishing and fisheries by-catch.The establishment of this Sanctuary for sharks, as well as marine mammals, was at the request of the Governments of Bonaire, Saba and St Eustatius.The local nature conservation and fisheries organizations are involved in the protection. The name of the Sanctuary “Yarari” is a Taíno Indian word, meaning ‘a fine place’.

Yarari sanctuary GIS data can be found at:

• Bonaire: Exclusive Economic Zone
• Saba and St.Eustatius: Exclusive Economic Zone

This month’s issue focuses on the Audubon’s Shearwater. Despite its resounding and unique call, this threatened bird often goes unnoticed on our islands, coming to shore at night to nest in remote locations. On Saba and St. Eustatius efforts are underway to confirm the presence of breeding shearwaters and locate their nests utilising predictive GIS modelling.

In the surrounding waters of the ABC islands an aerial survey took place last month to monitor the presence, density and distribution of marine mammals. An observation team from IMARES covered almost the entire Exclusive Economic Zone (EEZ) of the three islands, recording a number of marine mammal species as well as other megafauna.

Other content:

• ‘Breaking News’: Lionfish Control Efforts are Working on Bonaire and Curaçao!
• ‘Research of the Month‘: Aerial Marine Mammal Survey Around The Leeward Islands
• Audubon’s Shearwater: “Things That Go Bump In The Night”
• Overview of Research and Monitoring Efforts
• Calendar of Upcoming Events, Meetings and Workshops

Summary:

In November 2013 aerial surveys were conducted for the first time in the Exclusive Economic Zone of Aruba, Curaçao and Bonaire to evaluate aerial surveys as a tool for marine mammal surveys in these waters, and to assess the distribution and abundance of marine mammals. A secondary aim of these surveys was to collect data on the occurrence of other megafauna (e.g. sharks, rays, turtles) and seabirds. Marine mammals were assessed using distance sampling methods; for other species a strip transect method was applied.

Four marine mammal species were sighted, all of them cetaceans: Humpback Whale, Atlantic/Pantropical Spotted Dolphin, Bottlenose Dolphin and Rough-toothed Dolphin. The total number of individuals seen was 107. Numbers of sightings were too low to calculate densities and abundance estimates for any of the species recorded.

In addition to the marine mammals, sharks, rays, turtles and seabirds were recorded. Noteworthy observations include the first record of a (living) Basking shark and records of seabirds that are scarcely documented in these waters: Red-billed Tropicbird and either Great Skua or South Polar Skua. The number of sightings for these groups were too low to calculate densities and abundance estimates for any of the species recorded.

This survey was commissioned by the Dutch Ministry of Economic Affairs (EZ), and World Wildlife Fund The Netherlands. 

Summary:

Information on the distribution, abundance and ecology of marine mammal in the Wider Caribbean Region is scarce. This report aims at collating the on-going research in the Wider Caribbean Region, at identifying the most critical knowledge gaps that need to be addressed to inform and facilitate conservation actions and assess the most suitable research techniques to fill these knowledge gaps.

Numerous research activities aiming at marine mammals have been commenced by individual organisations as well as regional or even international collaborations throughout the Wider Caribbean over the past years. These efforts, ranging from visual to acoustic surveys, satellite telemetry, stranding response, and many more, provide valuable insight into important aspects of the ecology of marine mammals and show that the motivation and need to conduct research on marine mammals in the Caribbean waters is high. Due to lack of funds and capacity most current and past cetacean research in the region can be characterised as small-scale, low in sophistication, opportunistic, temporary and local which is a great limitation to the understanding required for proper conservation of this increasingly important resource in this tourism-oriented region. Consequently, if continued with the current level of capacity and expertise, the results will continue to remain limited. There is an urgent need to combine forces, work on a larger geographic scale and use new and innovative techniques if we want to move beyond the current patchwork in activities and understanding. Ideally, all on-going and suggested future research efforts should become integral parts of a joint international research strategy for the wider Caribbean.

The choice of research methods to be used, however, depends in large part on the questions to be answered. Knowledge on temporal and spatial scale of marine mammal occurrence in the Caribbean waters is essential for any effective management and conservation and should have first priority, followed by studies on the effect of anthropogenic activities on marine mammals. In the absence of adequate data on marine mammals in this region, but with cautious extrapolation of knowledge and experience gained in other parts of the world we suggest to concentrate research efforts on visual and acoustic surveys and monitoring, stranding networks and necropsy of stranded animals, along with photo ID and tissue sampling for genetic analysis. All these methods differ in terms of the aims for which they will be suitable. Therefore, the aims must be clear before choosing the method. Research on the diverse groups of marine mammals has to modular and collaborative such that it can be synergistic, provided that there is sufficient collaboration and communication between all parties involved.

Public outreach by involvement of local institutions, marine parks, tour operators as well as communication of any research plan and results to local, regional and international regulators, policy makers and public representatives, plays an equally important role in achieving management and conservation goals.

This report is part of the Wageningen University BO research program (BO-11-011.05-005) and has been financed by the Ministry of Economic Affairs (EZ) under project number 4308701020. 

From a global perspective, March has been busy when it comes to regulatory affairs with the CITES meeting in Bangkok, Thailand, in which worldwide protection for several shark species and manta rays was established and, closer to home, with the EEZ Meeting on Curaçao which will be showcased as the ‘Meeting of the Month’. This report is complemented by a short article on the importance of marine mammal conservation in the Dutch Caribbean.

Amongst others, you will find in this third issue:

• Overview of Research and Monitoring Efforts
• EEZ Meeting on Curaçao
• Marine Mammal Conservation in the Dutch Caribbean
• Dutch Caribbean Biodiversity Database update
• Shark Protection on CITES Convention
• Calendar of Upcoming Events, Meetings and Workshops

Abstract:

The Saba Bank is a large submerged carbonate platform of approximately 2,200 km2 in the Caribbean Sea which lies partially within the Exclusive Economic Zone of the Netherlands and partially within the territorial waters of Saba and St. Eustatius. It was declared a protected area by the Dutch Government on 15 December 2010 and has been registered as such in the Specially Protected Areas and Wildlife (SPAW) protocol of the Cartagena Convention for the Protection and Development of the Marine Environment of the Wider Caribbean. Applications for a Particularly Sensitive Sea Area (PSSA) at IMO and Ecological or Biological Significant Area (EBSA) at CBD are pending.

As part of the Saba Bank research program 2011-2016, commissioned by the Dutch Ministry of Economic Affairs (EZ), an expedition to the Saba Bank was conducted from 22 to 29 October 2011. The Saba Bank research program aims to obtain information on the biodiversity, key ecological processes and carrying capacity for commercial fisheries to facilitate sustainable management of the area. The primary objectives of the 2011 research expedition were to collect data on benthic and reef fish communities; sponges and nutritional sources of the sponge community; seabirds and marine mammals; water quality, water velocity and other physical parameters. A multidisciplinary team conducted video and visual surveys on benthos, fish and sponges during 10 SCUBA dives at 20-30m depth, while sea birds and marine mammals were surveyed by means of on-board visual surveys and acoustic data loggers. Water velocity and water quality were also measured on-board using an Acoustic Doppler Current Profiler (ADCP) and Conductivity, Temperature and Depth (CTD) device.

During the expedition 8 sponge species were collected and 37 scleractinian coral species and 85 fish species were identified.Fish biomass varied per site between 1.3 kg to 4.4 kg.
Part of the measurements on water velocity, water quality and benthic cover are still in the process of being analysed. Data collected will also be used as baseline for future monitoring and analyses of biodiversity and key ecological processes within the framework of the 2011-2016 research program. 

Abstract:

Aruba is one of the most densely populated islands in the Caribbean. However, very little is known about its cetaceans. In 2010 and 2011, a total of 19721 km (1686 h) boat-based surveys over nearshore transects resulted in 117 positively-identified sightings comprising eight species. New records are also added for one of three previously-documented species. Five additional species were documented from strandings or reports by others. This brings the total number of cetacean species identified in Aruban waters to 16, of which nine are authenticated here for the first time. Atlantic spotted dolphin (Stenella frontalis (N 1⁄4 59) and bottlenose dolphin (Tursiops truncatus) (N 1⁄4 33) were the most frequently observed species, with sightings of both year-round, followed by spinner dolphin (S. longirostris) and false killer whale (Pseudorca crassidens). Additional species recorded are pantropical spotted dolphin (S. attenuata), striped dolphin (S. coeruleoalba), common dolphin (Delphinus capensis), rough-toothed dolphin (Steno bredanensis), short-finned pilot whale (Globicephala macrorhynchus), killer whale (Orcinus orca), Risso’s dolphin (Grampus griseus), humpback whale (Megaptera novaeangliae), Bryde’s/Eden’s whale (Balaenoptera brydei/edeni), sperm whale (Physeter macrocephalus) and an unidentified beaked whale (Mesoplodon sp.). All cetaceans were sighted within 22 km of the coast in relatively shallow waters. Sighting rate was low (0.69 cetacean sightings per 100 km). Sightings of calves and neonates indicate that Aruba may be a nursing or breeding area for some species. The presence of several species of cetaceans in Aruba’s coastal waters year-round indicates that status and threat assessments are needed to protect them. 

1. Effective conservation management requires a solid understanding of social and economic factors, in addition to biological factors affecting what is to be conserved. Aruba is one of the most densely populated islands in the Caribbean and its already high number of tourists is still increasing. No commercial whale-watching operations are offered yet on the island. This provides a rare opportunity to document knowledge of and values concerning marine mammals before the introduction of whale-watching operations.

2. In 2010, a survey was conducted to investigate the awareness and attitudes of resident Arubans (n = 204) and tourists (n = 198) towards marine mammals and their conservation on Aruba. Knowledge of the local marine mammal community was low for both groups. Most participants would support more stringent legislation for protecting marine mammals in Aruba. Overall concern regarding threats to marine mammals was high and oil spills, chemical pollution, litter and sewage were identified as the most serious threats. A large proportion of residents (84.2%) and tourists (83.6%) were interested in, and willing to pay for, viewing marine mammals. Both groups preferred to see marine mammals in the wild rather than in captivity.

3. This is the first study that investigates the attitudes of people towards marine mammals and their conservation in a country that does not have marine mammal related tourism yet. This study suggests that strong support for marine mammal conservation issues does not critically depend on detailed knowledge of the local marine mammal community, or on the availability of whale-watching operations.

We here provide a synoptic overview and preliminary update of the marine mammals of the Dutch Caribbean EEZ based on 279 cetacean sighting and stranding records. The Dutch Caribbean EEZ is composed of two distinct sectors. One is centered around the leeward Dutch islands of Aruba, Bonaire and Curaçao (71,000 km2) while the other is centered around the windward Dutch islands of Saba, St. Eustatius and St. Maarten (22,000 km2). The previous principal review (of cetaceans) dating from 1998, was based on only 70 records from the leeward sector and confirmed the occurrence of some 13 species for Dutch Kingdom waters. Now, with a 4-fold increase in number of records, 19 species can be documented for the Dutch Kingdom waters (18 species in the leeward sector and 8 species in the windward sector).

The windward sector stands out for its large number of humpback whale sightings (45% of records) and may form part of its former (or current) calving grounds. This species remains relatively rare in the leeward sector (5% of records) and continues to be targeted by aboriginal fishing in its destination wintering grounds to the east, where the relict breeding population is having difficulty to rebound. The species is of growing interest to tourism in the region and urgently needs full protection from all fishing in the southern Caribbean. The leeward EEZ sector further lies down-stream from seasonal upwelling areas off Venezuela that support the largest fishery of the Caribbean. This sector stands out for its high occurrence of beaked whales and the Bryde’s whale. Marine mammal strandings are much more common here (26% of records) than in the northern sector (3% of records). Human induced mortalities (first suggested in 1974) and disturbance due to coastal tourism and recreation are key and growing concerns in the southern Dutch EEZ sector.

The marine mammal fauna of the Dutch Caribbean is evidently rich and varied but continues to suffer man-induced mortality and disturbance. Several nations, including the USA, the Dominican Republic and France, have recently established marine mammal sanctuaries in Caribbean waters. The Netherlands should consider doing the same.

...National Progress Reports presented at the 2002-10 meetings are accessible on the IWC website. Reports from previous years will also become available in this format in the future. The Committee reaffirms its view of the importance of national Progress Reports to its work in a number of sub-committee’s and recommends that the Commission continues to urge member nations to submit them following the approved guidelines (IWC, 1993b). Non-member nations wishing to submit Progress Reports are welcome to do so. It also draws attention to the need for those countries that do provide them to ensure that they are completed fully (e.g. see Items 7.3, 7.7, 14.5). Donovan reported that a prototype online submission system and database has been developed (IWC, 2011e, p.1) that will be trialled by a number of participants during and immediately after the meeting. It is expected that the online system can be used for next year’s national Progress Reports. The Committee welcomes this development. A summary of the information included in the Progress Reports presented this year is given as Annex O....