MARINE MAMMALS ST Introduction MARINE MAMMALS STRANDINGS in JAMAICA

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MARINE MAMMALS ST Introduction MARINE MAMMALS STRANDINGS in JAMAICA MARINE MAMMALS STRANDINGS IN JAMAICA by Christine O’Sullivan Jamaica Environment Trust Introduction Fig. 1: Melon -Headed Whale, Peponocephala electra , found at Donal d Quarrie High School found on June 2, 2005 With an estimated 28 species of marine mammals found in Jamaican waters it is imperative that a marine mammal stranding network be established. In the past three years three whales have stranded, two live and one dead. Both live strandings occurred with Pygmy Sperm Whales, Kogia breviceps , while a Melon-headed Whale, Peponocephala electra , was found dead behind Donald Quarrie High School on Jun e 2, 2005 (Fig. 1). While nothing could be done for the Melon-headed Whale, the Pygmy Sperm Whale live -strandings highlighted just how little is known, not only about marine mammals in general, but also about stranding procedures. Pygmy Sperm Whales are similar in appearance to Dwarf Sperm Whales, Kogia simus , making them difficult to distinguish. Distinguishing factors include the number of teeth, length, and dorsal fin length and position. Stomach contents indicate that they feed primarily on cephalo pods, crustaceans and fish. They can be found in tropical and temperate latitudes and Pygmy’s are thought to reside seaward of the continental shelf while Dwarf Sperm Whales may be more coastal. One feature they share is the use of a dark reddish-brown l iquid found in a sac within the lower intestine that is expelled in the water when they are startled. It is presumed that it is used either to deter predators or conceal the whale’s escape (Reeves, et al ., 2002). The only similarity that they appear to s hare with Sperm Whales, Physeter macrocephalus , is the spermaceti organ. It is only found in the head of these three whales and contains spermaceti, a liquid wax whose purpose is unknown (Reeves, et al . 2002). The strandings of the Pygmy Sperm Whales occurred in July 2004 and on March 31, 2006. While the circumstances surrounding both strandings differed they were both marred by lack of expertise and indecision. These strandings highlighted the need for an established marine mammal stranding network with the ability to quickly and competently respond to stranding events. Case studies Fig. 2: Pygmy Sperm Whale, Kogia breviceps , neonate that stranded in July 200 4 The National Environment and Planning Agency (NEPA) responded to t he first stranding, which occurred in Portland in July 2004. Upon arrival it was noted that the animal had been recovered by residents and placed in a container with salt water (Fig. 2). The water was routinely changed while they waited for NEPA to arrive. The animal appeared to be a neonate ( newborn ), which was indicated by the presence of papillae on the tongue as well as vestigial hairs. The animal had several cuts and scrapes on its body, was extremely small and could be lifted and held by one perso n. However, no measurements were taken. According to residents it had swum to shore, attempted to go back out to sea and then returned. At that point it was recovered by the residents, who noted that a pod ( group of whales or dolphins) had been seen off shore, before eventually leaving the area. NEPA staff members were eventually joined by a team from Dolphin Cove, who moved the animal to a shallower, calmer beach to determine the next course of action. While there, an attempt was made to refloat the a nimal but it was unsuccessful. The decision was finally taken to take the animal to Dolphin Cove in Ocho Rios and care for it there. The animal died early the next morning. Fig 3: Pygmy Sperm Whale before refloating attempt On March 31, 2006 NEPA received a call that a whale had stranded in Morant Bay, St. Thomas and a joint team from NEPA and the Jamaica Environment Trust (JET) responded to the call. Upon arrival it was determined that the individual was a male Pygmy Sperm Whale (Fig. 3). It did not appear to be malnourished or dehydrated but had several cuts and scratches along its bo dy, particularly on its stomach (Fig. 4). All the cuts were superficial and would not have caused the stranding event. They appeared, instead, to have occurred when the animal swam through a nearby coral reef. An antiseptic was placed on the scratches a nd the animal was carried further offshore and held in the water. Several attempts to refloat the animal were made but after each attempt the animal returned to shore and it was decided that the animal needed to be euthanized. However, before the veterin arian could arrive, the animal died. A partial necropsy (autopsy performed on animals) was performed but a definitive cause of death could not be determined. Measurements were taken by the Natural History Division, Institute of Jamaica and the animal was 1.87 metres in length indicating that it was a sub -adult. Fig. 4: Scratches on the stomach of the Pygmy Sperm Whale Problems associated with each stran ding In both instances, while the death of each animal was inevitable, the care provided for each animal could have been different shortening the amount of time that they suffered. In the first case a chain of command should have been established based on marine mammal stranding experience. Decisions therefore would have been made based on training in stranding protocol and experience in marine mammal strandings, rather than emotion. Had this occurred the Pygmy Sperm Whale neonate would have been euthanized, and never transported to Dolphin Cove, since neonates are unable to survive without their mothers. Had this decision been taken, its suffering would not have been prolonged. In both cases, however, the use of euthanasia would have been determined by the identification of a veterinarian. While a veterinarian was identified in the second case this only occurred after several other vets were unable to respond. Had a stranding network been established willing veterinarians would have already been identified and the response time would have been much shorter. A stranding network would have also trained individuals around the island providing them with the necessary training to respond to each stranding before the NEPA and JET staff arrived, and then assist them upon arrival. Much of the equipment necessary was not immediately available and some items had to be purchased before arriving at the scene. While some materials could be purchased easily, other equipment cannot be, though they are instrumental in caring for the animals. During the second stranding the rescue team had to improvise in order to effectively care for the animal. A proposal for a marine mammal stranding network is currently being developed by the Jamaica Environment Trust in order to ensure that interested persons around the island can be trained in stranding procedures and stranding equipment will be provided in the event of a stranding. This will ensure that all stranded animals will receive the best possible care. Stranding events In the event of a stranding immediate action can be taken in order to care for the animal(s). This includes: • Report the incident to the National Environment and Planning Agency at 754-7540. • Support the animal in an upright position and dig trenches under the pectoral fins. • Cover the animal with wet sheets or towels (even seaweed) and keep it moist by spraying or dousing with water. • Do NOT cover, or let any water pass down the blowhole (sited on top of the animal’s head). This will cause the animal great distress and could even kill it. • Every movement around a stranded animal should be quiet, calm and gentle. Excessive noise and disturbance will only stress it further. • Do not attempt to drag the animal. • Do not pull on fins or tail. • Erect a shade to prevent it from overheating. Source: Cetacean Research and Rescue Unit: www.crru.org.uk British Divers Marine Life Rescue (BDMLR): http://www.bdmlr.org.uk/pages/main.html Literature Cited: Reeves, R.R., B.S. Stewart, P.J. Clapham, and J.A. Powell. 2002. National Audubon Society Guide to Marine Mammals of the World. Alfred A. Knopf. New York. For further information contact: Christine O’Sullivan Marine Mammals Specialist Jamaica Environment Trust 11 Waterloo Road Kingston 10 (876) 960-3693 [email protected] www.jamentrust.org .
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