The European turtle dove (Streptopelia turtur) is classified as vulnerable by the IUCN. In this context, it is important to explore the factors affecting its abundance and the ways in which it can be effectively managed for conservation. This study compares the distribution of this dove in Spain and Morocco. These countries, which are separated by the Strait of Gibraltar, are each occupied by a different subspecies (i.e. Streptopelia turtur turtur in Spain and S. t. arenicola in Morocco) that may be adapted to different environmental conditions. Such differentiation could result in differences in the species’ abundance between the two countries. The occurrence of this dove was assessed by means of road counts, and the resulting records were used to explore the niche overlap between the two subspecies. The niches of both populations overlapped, suggesting the selection of similar environmental conditions in the two countries. However, the species occurred more frequently in Morocco than in Spain. To study the potential role of local effects on the observed differences in abundance, 494 sampling points were surveyed in four different sectors of Spain and Morocco. These additional counts indicated that, after controlling for the effect of local habitat structure and climate, the European turtle dove is more frequent in Morocco than in Spain. Differences between the two countries, in relation to hunting pressure, agricultural intensification and the abandonment of marginal cultures and woodlands, could account for the observed transboundary differences in the abundance of European turtle dove and help to explain its severe decline in Spain.

中文翻译：

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欧洲斑鸠（Streptopelia turtur）在西南古北缘的分布：跨界差异和保护前景

IUCN将欧洲斑鸠（Streptopelia turtur）归类为易受伤害物种。在这种情况下，重要的是要探索影响其丰富度的因素以及有效管理其保存方式。本研究比较了这只鸽子在西班牙和摩洛哥的分布。这些国家被直布罗陀海峡隔开，每个国家都被不同的亚种所占据（例如，西班牙的链球菌属和阿根廷的S. t。arenicola在摩洛哥），可能会适应不同的环境条件。这种分化可能导致两国之间物种的丰度差异。通过道路计数来评估这只鸽子的发生，并使用所得记录来探索两个亚种之间的生态位重叠。两种种群的生态位重叠，这表明两国选择了相似的环境条件。但是，该物种在摩洛哥比在西班牙更常见。为了研究局部效应对观测到的丰度差异的潜在作用，在西班牙和摩洛哥的四个不同地区对494个采样点进行了调查。这些额外的数字表明，在控制了当地栖息地结构和气候的影响之后，欧洲海龟鸽子在摩洛哥比在西班牙更常见。两国之间在狩猎压力，农业集约化和边缘文化和林地被遗弃方面的差异可以解释观察到的欧洲海龟鸽子数量的跨界差异，并有助于解释其在西班牙的严重下降。