Dolphin of the month - Harbour Porpoise
A little guy who needs a lot of help. The harbour porpoise is one of the smallest creatures in the ‘whale and dolphin family, just over a metre long and rarely shows his face being shy and likes to keep a low profile.
The English word ‘porpoise’ is derived from the Latin word for pig – porcus. The harbour porpoise used to be referred to as the ‘puffing pig’ because of the sneeze-like puffing sound it sometimes makes when it breathes. Harbour porpoises are the only member of the porpoise family found in European waters. Both sexes are reported to live up to some 23 years but few survive past 12 years of age. Four subspecies of harbour porpoise are recognised; P. p. phocoena in the North Atlantic; P. p. vomerina in the eastern North Pacific; P. p. relicta in the Black Sea; and an unnamed subspecies in the western North Pacific.
Harbour porpoises are found in coastal waters of the sub-Arctic, and cool temperate waters of the North Atlantic and North Pacific. They frequently visit shallow bays, estuaries, and tidal channels less than 200m in depth, and have been known to swim up rivers; the majority of sightings occur within 10km of land. Due to seasonal prey movements, they usually move inshore in the summer and offshore in the winter. There is some evidence of north-south migrations. Numbers of harbour porpoises in some areas have declined in the past few decades due to human activities and the global population is unknown although estimates have been suggested. The IUCN regards the species overall as of Least Concern (2008) although the subspecies found in the Black Sea is listed as Endangered and the population in the Baltic Sea is considered Critically Endangered. Historically, harbour porpoises were hunted in large numbers but the biggest current threat to harbour porpoises throughout their range is incidental capture in fishing nets with thousands of casualties each year.