Narwhal  (Monodon monoceros)

By-catch: In the fishing industry, the part of the catch made up of non-target species.
Cetaceans: A group comprising all whale species; therefore including dolphins and porpoises.
Dorsal fin: The unpaired fin found on the back of the body of fish, or the raised structure on the back of most cetaceans.
Gestation: The state of being pregnant; the period from conception to birth.
Maxillary: In vertebrates, of or relating to the maxilla, which is the posterior bone of the upper jaw. In certain arthropods, the maxillae are paired structures that act as mouthparts.
Secondary sexual characteristic: A characteristic, other than the reproductive organs, that defines males and females.

1. IUCN Red List (November, 2008)
   http://www.iucnredlist.org
   
2. Macdonald, D. (2001) The New Encyclopedia of Mammals. Oxford University Press, Oxford.
   
3. Culik, B.M. (2002) Review on Small Cetaceans: Distribution, Migration and Threats. UNEP/CMS Secretariat, Bonn, Germany. Available at:
   www.cms.int/reports/small_cetaceans/index.htm
   
4. MarineBio.org (April, 2005)
   http://marinebio.org/species.asp?id=336
   
5. CITES (April, 2005)
   http://www.cites.org
   
6. CMS (April, 2005)
   http://www.cms.int
   
7. Berne Convention (April, 2005)
   http://www.coe.int/t/dg4/cultureheritage/conventions/bern/default_en.asp
   
8. Heide-Jørgensen, M.P. (2008) Pers. Comm.
   
9. Cetaceans of the World (May, 2005)
   http://www.sci.tamucc.edu/tmmsn/29Species/MoreSpec/narwhal.html