GROSS-ANATOMY OF THE GASTROINTESTINAL SYSTEM OF HARP SEALS (PHOCA-GROENLANDICA)

The gross anatomy of the gastrointestinal system of 12 harp seals (Pho ca groenlandica) was investigated. Harp seals have a typical carnivore monogastric stomach. The tissue wet weight of the stomach of harp sea ls represented 27.01 (S.D. 3.99)% (n = 12) of the total gastrointestin al tract (GI-tract). All animals were killed while resting on the ice, and had empty stomachs, but when expanded with water to a 30 cm press ure the stomach contained 0.60 to 1.60 litres, representing 1.00 (S.D. 0.26)% (n = 12) of the body mass. The small intestine ranged in lengt h from 20.44 to 25.32 m, being 14.36 (S.D. 1.58) times the body length , and the tissue wet weight constituted 67.61 (S.D. 4.55)% of the tota l GI-tract (n = 12). Both caecum and colon were short, maximally 5 and 78 cm, respectively, being 0.022 (S.D. 0.005) and 0.38 (S.D. 0.06) ti mes the body length (n = 12). The caecum tissue wet weight was only 0. 18 (S.D. 0.04)% of the total GI-tract weight, while the colon tissue w et weight contributed to 5.33 (S.D. 1.19)% (n = 12). It is concluded t hat harp seals have relatively long intestines compared to minke whale s eating a comparable diet in the North Atlantic Ocean.