The Essex Naturalist
47
Cetaceans stranded on the Essex coast
John Dobson
16, Westerings, Bicknacre, Danbury, Essex CM3 4ND.
Summary
Since the middle of the 19th century, the stranding of cetaceans along the Essex
coast has been recorded in a number of journals including Zoologist and the Essex
Naturalist. From that time until 1997, there have been 96 strandings of
cetaceans involving 12 species. The most frequently reported was the harbour
porpoise constituting 49% of all records. Although there has been a rise in the
number of strandings during the last decade, this may be due to increased
observer activity or a greater vulnerability of visiting cetaceans to the conditions
currently present off the Essex coast, rather than evidence of an increase in the
population of these mammals. For two species - the white-beaked dolphin
(1977) and northern bottlenose whale (1939) - the majority of records occurred
during one year, suggesting that a larger number were present offshore at the
time. Strandings occurred in all months with peaks in April and September.
Introduction
The presence of cetaceans in Essex waters comes as a surprise to many people yet
the thirteen species recorded during the last 150 years account for over 20% of
the mammal species occurring in the county. Many of the reports refer to
animals that have been stranded along the coast, details of which have been
obtained from a number of sources. During the 19th century, and prior to 1912,
reports of strandings appeared in the Essex Naturalist and the Zoologist. Laver
(1898) compiled data on all Essex mammals including anecdotal information on
the ultimate fate of many stranded cetaceans. Historical records often refer to
animals being "captured". Where clarification is not available, it has been
assumed that the specimen was "alive, but beached" prior to being killed and has
therefore been included in this review. From 1912 a national recording scheme
was initiated whereby details of strandings were forwarded to the British
Museum (Natural History) from the Receivers of Wreck. Between 1913 and
1992, details of the findings were subsequently published (Harmer, 1914, 1927;
Fraser, 1934, 1946, 1953, 1974; Sheldrick, 1989, 1994). Information relating to
cetaceans stranded in Essex from 1993 up to December 1997 has been kindly
provided by the Marine Services Division of the British Museum.
Species accounts
Fin whale (Balaenoptera physalus) L.
The fin whale is the largest mammal species to have occurred in Essex and there
are records of five strandings. Due to the state of its decomposition, the female
that stranded near Barking Creek "burst" two days after stranding "and disclosed