Bycatch and fishing entanglement [ 33 ] are common sources of injury , with 64 % of entangled pinnipeds in one study deemed seriously injured [ 34 ] . Box cutters can safely remove entanglement material , and antibacterial solutions such as chlorhexidine can be used on topical wounds of shallow depth . Any wound that extends deeper than the blubber layer will require more intensive treatment [ 12 ] .
Human disturbance ( e . g . boats , beach walkers , dogs and drones ) is a significant cause of pup and mother separation [ 33 , 35 ] . Disturbance can also cause the animals to stampede into the water , resulting in physical injury to pups . Winter storms can disrupt the grey seal pup season , causing premature separation of pups from mothers , which leaves young animals malnourished [ 36 ] .
If immediate re-release is deemed appropriate , the release should always be attempted at or near the point of capture , unless doing so would harm the animal [ 21 ] .
Cetaceans
The order of Cetacea includes Odontoceti ( toothed whales and dolphins ) and Mysticeti ( baleen whales ) [ 37 ] .
Cetaceans observed around the UK coast
Of the cetaceans that pass frequently or visit our shores , the harbour porpoise , short-beaked or common dolphin , long-finned pilot whale , fin whale and minke whale are the species which most often become stranded [ 38 ] . Harbour porpoises are coastal species and if they become stranded alone are likely to be in poor health . However , short-beaked dolphins , long-finned pilot whales , fin whales and minke whales ( like Atlantic white-sided dolphins , beaked dolphins , Risso ’ s dolphins and orcas ) are pelagic species and may become disorientated if they travel too close to the coastline , but are likely to be healthy [ 12 , 39 ] .
As the UK does not have its own rescue or rehabilitation centres for cetaceans , the options for live strandings are flotation or euthanasia [ 40 ] . In one study , the success rates for transported , rehabilitated and released animals were between 2 % and 35 %, so the lack of cetacean rehabilitation centres is likely to continue [ 41 ] . Flotation involves a large team safely using an inflatable pontoon ( Figure 6 ) to support the weight of a cetacean , allowing its movement back into the sea after assessment [ 12 ] .
The consequences of strandings
Mass strandings often consist of pelagic species , while single strandings can be either coastal or pelagic species . The outcome relies on the initial assessment and triage of the animal , often by a British Divers Marine Life Rescue ( BDMLR ) medic . This assessment is based on clinical signs , including the BCS , which is determined by
Figure 6 . A model whale in a flotation pontoon .
the convex profile of the epaxial section , ventrodorsal to the dorsal fin [ 42 ] . This and other assessments are often impeded by the environmental and physiological impact of the stranding . These life-threatening changes only worsen the longer the animal is stranded [ 41 ] .
Muscle damage , scoliosis , organ failure ( including liver damage ) and pneumonia are common where re-flotation has been attempted after a single-animal stranding , which often compounds the original cause of the stranding .
If a cetacean is large or has beached on rocks , the prognosis for survival is significantly reduced [ 41 ] due to the concentrated pressure on its organs , and the likelihood of injury in an attempt to move the animal [ 38 ] .
Cetacean assessment and handling
It is vital that any movement of a cetacean is only carried out by trained individuals , as ‘ inappropriate action , despite the good intentions driving it , can exacerbate the animal welfare problem and potentially have more serious consequences ’ [ 43 ] . A mask , goggles and latex gloves should be worn when handling cetaceans , to limit the spread of zoonotic diseases [ 41 ] through direct contact and via the vapour dispersed in exhalations from the blowhole [ 12 ] .
Stranded cetaceans should first be rolled on to their bellies , tucking their flippers into their sides to stop them being crushed . Once stable , small holes should be dug into the sand to allow the flippers to drop into a natural position [ 12 ] . When out of the water , cetaceans overheat and dry out quickly , so it is paramount to keep spraying them with water , or cover them with a damp sheet ( avoiding the blowhole ) [ 38 ] .
Significantly larger species , such as sperm whales , humpback whales , fin whales and sei whales , are not suitable for relocation due to their size so , unless the tide comes in , stranding usually results in their death [ 12 ] .
Volume 38 ( 2 ) • April 2023
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