National Institute of Water and Atmospheric Research Limited, 301 Evans Bay Parade, Hataitai, Private Bag 14901, Wellington 6021, New Zealand.
J Fish Biol. 2012 Apr;80(5):1546-62. doi: 10.1111/j.1095-8649.2012.03255.x. Epub 2012 Mar 20.
The diet of smooth skate Dipturus innominatus was determined from examination of stomach contents of 321 specimens of 29·3-152·0 cm pelvic length, sampled from research and commercial trawlers at depths of 231-789 m on Chatham Rise, New Zealand. The diet was dominated by the benthic decapods Metanephrops challengeri and Munida gracilis, the natant decapod Campylonotus rathbunae and fishes from 17 families, of which hoki Macruronus novaezelandiae, sea perch Helicolenus barathri, various Macrouridae and a variety of discarded fishes were the most important. Multivariate analyses indicated the best predictors of diet variability were D. innominatus length and a spatial model. The diet of small D. innominatus was predominantly small crustaceans, with larger crustaceans, fishes and then scavenged discarded fishes increasing in importance as D. innominatus got larger. Scavenged discards were obvious as fish heads or tails only, or skeletal remains after filleting, often from pelagic species. Demersal fish prey were most frequent on the south and west Chatham Rise, in areas where commercial fishing was most active. Dipturus innominatus are highly vulnerable to overfishing, but discarding practices by commercial fishing vessels may provide a positive feedback to populations through improved scavenging opportunities.
在新西兰查塔姆海隆，深度为 231-789 米处，通过研究和商业拖网渔船，对 321 个 29.3-152.0 厘米臀长的光滑星鲨样本进行了胃内容物检查，以确定其饮食结构。其食物主要来源于底栖十足目甲壳动物马氏真龙虾和美丽滨蟹、洄游十足目甲壳动物拉氏短桨蟹和 17 科鱼类，其中重要的鱼类有真鳕 Macruronus novaezelandiae、海鲈 Helicolenus barathri、各种长尾鳕科鱼类和各种废弃鱼类。多元分析表明，影响饮食变化的最佳预测因子是 D. innominatus 的长度和空间模型。小 D. innominatus 的饮食主要是小型甲壳类动物，随着 D. innominatus 的体型增大，甲壳类动物、鱼类和随后的废弃鱼类的比例逐渐增加。废弃的鱼通常只有鱼头或鱼尾，或者是经过去骨后的骨骼残骸，主要来自中上层鱼类。在商业捕鱼活动最活跃的查塔姆海隆南部和西部，底栖鱼类猎物最为常见。D. innominatus 极易受到过度捕捞的影响，但商业渔船的丢弃做法可能会通过改善觅食机会，对种群产生积极的反馈。
