A mid-water otter trawl fishery targeting Illex illecebrosus operates in the northwestern Atlantic Ocean. The majority of I. illecebrosus are captured during mid-June to early September. Diel migratory behavior limits the fishery to daylight hours, but does the time-of-day affect catch? Illex illecebrosus were collected from each tow from a subset of the trawler fleet fishing on the outer continental shelf of the Mid-Atlantic Bight over the fishing season to determine the influence of time-of-day on catch. The male-to-female ratio was not influenced by time-of-day of capture. The size–frequency​ distribution of I. illecebrosus varied between tows within the same day of capture. Time-of-day of capture influenced average weight and, to a lesser degree, mantle length. Shorter and lighter squid were caught in the middle of the day. Larger and heavier squid were caught during the morning and afternoon. Data collection on commercial fishing vessels required that squid be frozen onboard, thawed onshore, and then weighed and measured. Differences between fresh and frozen squid were significant, but small, which permitted combining fresh and frozen measurements from different boats to track temporal and spatial trends in squid size. As time-of-day differences in catch were significant, obtaining unbiased size data from fishing vessel-based reports requires that samples be collected from the morning, afternoon, and evening tows during the trip.

针对大西洋鸢尾的水獭拖网捕捞活动在大西洋西北部开展。我的大多数。在6月中旬至9月上旬捕获了illecebrosus。Diel的迁徙行为将渔业限制在白天，但是一天中的时间会影响产量吗？在捕鱼季节中，从大西洋中部大西洋沿岸大陆架上一部分拖网渔船捕捞的每根拖网中收集了Illex illecebrosus，以确定一天中的时间对渔获量的影响。男女比例不受捕获时间的影响。I的大小-频率分布。鸢尾在捕获的同一天内，拖曳之间会发生变化。一天中的捕获时间影响平均重量，并在较小程度上影响地幔长度。当天中间捕获了更短更轻的鱿鱼。早晨和下午捕获了更大更重的鱿鱼。商业捕鱼船的数据收集要求将鱿鱼在船上冷冻，融化，然后称重并测量。鲜鱿鱼和冷冻鱿鱼之间的差异很大，但差异很小，这允许结合使用不同船只的鲜鱿和冷冻测量值来跟踪鱿鱼大小的时空趋势。由于每天的捕获量差异很大，因此要从基于渔船的报告中获取无偏差的大小数据，需要在旅途中的早晨，下午和晚上拖曳收集样品。