As an omnivorous primate I have no issue with conspecifics who hunt to feed their bodies. I do, however, have serious complaints against those who hunt only to feed their egos. I believe it is shameful for trophy hunters to kill animals which are no threat to them and that they do not plan on eating. Judging by the pressure being put on airlines to refuse to transport hunting trophies, many people agree with me.
Thus far most anti-trophy hunting sentiment has only been extended on behalf of land animals, which is unfortunate, because trophy hunting of fish and marine invertebrates may be even more environmentally problematic. The desire to kill the largest fish, lobster, or abalone, not only likely leads to selection for these species to become smaller (Conover 2000; Hamilton 2007) but also jeopardizes the continued survival of these species. Unlike most trophy hunted land animals, who cease growing after sexual maturity and often do not show very clear relationships between female body size and fertility (Green and Rothstein 1991; Guinet et al. 1998) most fish and marine invertebrate species continue growing throughout their lives and it is the largest oldest females who produce the most eggs. This means that marine trophy hunters are likely to kill a population’s most important breeders as they attempt to inflate their egos by killing the largest individuals. While land-based hunters can try to compensate for this by ‘chivalrously’ only killing males, most sea hunters cannot tell the difference between live male and female tuna, billfish, snappers, or groupers.
Furthermore, attempting to apply land-based big game hunting ethics to fish can be extremely problematic. Mammals as a rule do not change sex, but many fish do. In species like the California sheephead, fish begin their lives as females and metamorphose to males once they grow large enough to take control of a harem. When a harem male is killed, one of the females changes sex to replace him, but the change is not instantaneous and may leave the harem without mating opportunities for several months. In this case targeting the largest and most impressive fish may be more unsustainable than hunting ‘unchivalrously’.
Clearly while fish do not inspire as much human sympathy as land animals do, they are no more morally acceptable as corpses to lay on the altar of the ego and using them as such may be even more ecologically damaging than using land animals for this purpose. Those of us who pursue fish with poles or spears must afford our prey the proper respect. We must not kill more than we can eat fresh, we must show the intelligence and humility to spare the best breeders, and we must understand that true predators hunt for sustenance, not for self-aggrandizement.
Conover DO. 2000. Darwinian fishery science. Mar Ecol Prog Ser 208, 299-213 darwinianfisheriesscience
Green WCH, Rothstein A. 1991. Trade-offs between growth and reproduction in female bison. Oecologia 86, 521-527 bisonfertility
Guinet C, Roux JP, Bonnet M, Mison V. 1998. Effect of body size, body mass, and body condition on reproduction of female South African fur seals (Arctocephalus pusillus) in Namibia. Can. J. Zool. 76, 1418-1424 fursealfertility Hall, J. 31-Mar-2014.
“Spearfishing: Blue Water Big Game”. http://www.outdoorlife.com/blogs/gone-fishin/2014/03/spear-fishing-speargun. Accessed 11-Jun-2015
Hamilton SL, Caselle JE, Standish JD, Schroeder DM, Love MS, Rosales-Casian JA, Sosa-Nishizaki O. 2007. Size-selective harvesting alters life histories of a temperate sex-changing fish. Ecological Applications 17(8), 2268-2280 sheepheads
 Obviously some humans do have gender identities that differ from the sex they were assigned at birth and I support their right to be identified as the gender of their choice, but medical science has not advanced far enough to enable mammals, human or otherwise, to switch from producing eggs to sperm or vice versa.
 No fish has ever spawned in a freezer.