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首页> 外文会议>International Symposium on the Management and Biology of Dogfish Sharks >Population Estimates of Spiny Dogfish Aggregations Overwintering South of Cape Hatteras, North Carolina, Using an Area Density Method
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Population Estimates of Spiny Dogfish Aggregations Overwintering South of Cape Hatteras, North Carolina, Using an Area Density Method

机译：利用面积密度法，北卡罗来纳州哈特拉斯南部越来越多遍冬季捕鸟犬聚集的人口估计

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Little information is available about the coastal distribution of spiny dogfish Squalus acanthias south of Cape Hatteras, North Carolina, and whether these fish are an extension of the population that overwinters in continental shelf waters off the North Carolina Outer Banks north of Cape Hatteras, or a separate population that remains south of Cape Hatteras. A coastal roaming survey was conducted in February and March 1999 from south of Cape Hatteras to the South Carolina state line to estimate thenumber of dogfish in coastal waters. Fish aggregations were located by sonar, and a commercial-grade sink gill net of seven different mesh sizes was deployed in waters to assess whether the aggregations were dogfish. Six large dogfish aggregations were located in shallow (10-16 m) coastal waters of Raleigh Bay, Onslow Bay, and Long Bay, covering an estimated surface area of about 66,922 ha. Two additional sets marked by sonar were not dogfish aggregations. No dogfish were caught in exploratory deepwatersets (46—55 m). Using a sensitivity analysis, total population size of all aggregations was estimated at 1.102 to 2.223 million individuals or 2.470 to 4.984 million kg. The sex ratio was 27.1:1 females to males. Aggregations were located near the bottom at a temperature range of 10.4°C to 15.7°C. Temperatures varied little vertically through the water column; laterally temperatures varied by less than 1°C for five of six aggregations. The largest aggregation, in Raleigh Bay, was exposed to the greatest spatial variability in temperature (3.6°C across 15,135 ha). This is perhaps a result of its proximity to the Gulf Stream at this time of year. We believe that dogfish south of Cape Hatteras during the winter are a small portion, probably less than 1%, of the U.S. migratory stock.
机译：关于哈特拉斯州北卡拉斯岛南部的沿海分布的沿海分布，北卡罗来纳州的沿海分布以及这些鱼是否是北卡罗来纳州北卡罗来纳州北部的南卡罗来纳州外滩的横穿者的延伸独立的人口仍然是哈特拉斯南部的。沿海漫游调查是在1999年3月的1999年3月从海角到南卡罗来纳州的州线进行，以估计沿海水域的Davfish Umber。鱼类均位于Sonar，七种不同网格尺寸的商业级水槽荨麻网部署在水域中，以评估汇总是否是鲨鱼。六大鲨鱼聚集位于岩岩湾，Onslow湾和长湾的浅（10-16米）沿海水域，覆盖估计约66,922公顷的表面积。由声纳标记的两个额外的组不是鲨鱼聚集。没有狗在探索深水（46-55米）中陷入困境。使用敏感性分析，所有汇总的总人口大小估计为1.102至22.223亿人，或2.470％至49.84亿公斤。性别比例为27.1：1个女性对男性。聚集在底部附近，在10.4℃至15.7℃的温度范围内。温度通过水柱垂直变化;横向温度为六个聚集中的五个变化小于1°C。在Raleigh Bay中，最大的聚集在罗利湾，暴露于温度最大的空间变异（3.6°C，横跨15,135公顷）。这可能是在一年中的这个时候对海湾溪流的邻近。我们认为，在冬季，哈特拉斯州的鲨鱼南部是美国迁徙股票的一小部分，可能不到1％。

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