. The Canadian field-naturalist. 1990 HOUSTON: Status of Blainville's Beaked Whale 119 160 MO 120 100 80 60 iO 20 0. Figure 2. Distribution of Blainville's Beaked Whale. to be a threat in the future. Since small whale fisheries are opportunistic and indiscriminate as to species, they tend to be multispecies fisheries. In such fisheries one may think that a falling catch per unit effort would not influence future catch effort. However, many of the species in such fisheries are rare and it cannot be assumed that any future exploitation would, in the longterm, be inconse- quential (see Mitchell 1
. The Canadian field-naturalist. 1990 HOUSTON: Status of Blainville's Beaked Whale 119 160 MO 120 100 80 60 iO 20 0. Figure 2. Distribution of Blainville's Beaked Whale. to be a threat in the future. Since small whale fisheries are opportunistic and indiscriminate as to species, they tend to be multispecies fisheries. In such fisheries one may think that a falling catch per unit effort would not influence future catch effort. However, many of the species in such fisheries are rare and it cannot be assumed that any future exploitation would, in the longterm, be inconse- quential (see Mitchell 1975b). At present, the species is probably inherently protected by its rarity and pelagic habits. Special Significance of the Species Most of what is known of ziphiids in Canadian waters comes from the few specimens stranded here. Blainville's Beaked Whale has not as yet been recorded from British Columbia but is known from Nova Scotia. The species is not known to have been taken by commercial whalers and probably not by coastal fisheries because of its pelagic habits. It is doubtful that the species or parts or derivatives would show up in international trade as there is no demand. Blainville's Beaked Whale could be confused with Cuvier's Beaked Whale {Ziphius cavirostris) where the ranges overlap. Identification requires an expert. Evaluation Blainville's Beaked Whales are medium-sized cetaceans which are widely dispersed in tropical and sub-tropical waters. Mitchell (1975a,b) has indicated that most species of the genus are probably not abundant and that even moderate exploitation could impact negatively on existing populations. The species is not known from British Columbia and is only rarely seen on the east coast. Given the above, and the fact that Canadian distribution is on the periphery of the range, the species would appear to be rare in Canadian waters. As it is not under any threat in Canada there is no reason to consider a COSEWIC status designation for the species
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