1. This study presents data on a local population of short‐beaked common dolphin monitored in the waters off Ischia Island (Gulf of Naples, Italy) over a 16‐year period (2000‐2015). We examine dolphin occurrence and distribution and perform photoidentification analysis.
2. The data presented support the hypothesis that the waters around Ischia Island represent a feeding area, as well as a calving and an important nursery area for this local population, providing favourable conditions in which to give birth and raise calves.
3. The levelling‐off of the photoidentification curves together with the continuous decline of the encounter rate lead us to believe that the area has been a hotspot for a local population (mainly resident) for years and that now this population is dying (has died) or is moving (has moved) to other locations.
4. Several expanding human activities at sea have the potential to impact on the common dolphin in the study area, the most significant possibly being habitat disturbance and degradation (including traffic and noise pollution) and overexploitation of food resources by the fishery.
5. The data presented in this study offer a strong argument for explicit and urgent population‐specific conservation and management strategies to be developed and applied locally for common dolphins, considering that they rely on the region for important biological processes.

中文翻译：

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短喙普通海豚（Delphinus delphis）在伊斯基亚岛（意大利那不勒斯湾）附近海域的下降

1. 本研究提供了在16年期间（2000-2015年）在伊斯基亚岛（意大利那不勒斯湾）附近海域监测的短喙普通海豚当地种群的数据。我们检查海豚的发生和分布，并进行光识别分析。
2. 所提供的数据支持这样的假说，即伊斯基亚岛周围的水域代表了该地区人口的觅食区域，同时也是产犊和重要的育苗区，为分娩和饲养犊牛提供了有利条件。
3. 光识别曲线的趋于平缓以及相遇率的持续下降使我们相信该地区多年来一直是当地人口（主要是居民）的热点，而现在该人口正在死亡（已死亡）或正在移动（已移动）到其他位置。
4. 海上几种人类活动正在扩展，有可能影响研究区域的普通海豚，其中最重要的可能是栖息地的干扰和退化（包括交通和噪声污染）以及渔业对食物资源的过度开发。
5. 这项研究提供的数据有力地支持了明确和紧急的针对特定海豚的保护和管理策略，这些策略应在本地针对普通海豚开发和应用，因为它们依赖于该地区进行重要的生物过程。