Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT, United States.
Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT, United States.
PeerJ. 2023 Feb 20;11:e14928. doi: 10.7717/peerj.14928. eCollection 2023.
Orchid bees are abundant and widespread in the Neotropics, where males are important pollinators of orchids they visit to collect fragrant chemicals later used to court females. Assemblages of orchid bees have been intensively surveyed in parts of Central America, but less so in Belize, where we studied them during the late-wet and early-dry seasons of 2015-2020.
Using bottle-traps baited with chemicals known to attract a variety of orchid bee species, we conducted surveys at sites varying in latitude, historical annual precipitation, elevation, and the presence of nearby agricultural activities. Each sample during each survey period consisted of the same number of traps and the same set of chemical baits, their positions randomized along transects.
In 86 samples, we collected 24 species in four genera: (16 species), (3), (3), and (2). During our most extensive sampling (December 2016-February 2017), species diversity was not correlated with latitude, precipitation, or elevation; species richness was correlated only with precipitation (positively). However, a canonical correspondence analysis indicated that species composition of assemblages varied across all three environmental gradients, with species like , and most common in the drier north, and , and more so in the wetter southeast. Other species, such as and , were common throughout the area sampled. Mean species diversity was higher at sites with agricultural activities than at sites separated from agricultural areas. A Chao1 analysis suggests that other species should yet be found at our sites, a conclusion supported by records from adjacent countries, as well as the fact that we often added new species with repeated surveys of the same sites up through early 2020, and with the use of alternative baits. Additional species may be especially likely if sampling occurs outside of the months/seasons that we have sampled so far.
兰花蜂在新热带地区数量丰富且分布广泛，雄性兰花蜂是它们访问的兰花的重要传粉者，它们采集芳香的化学物质，后来用于吸引雌性。兰花蜂的集合在中美洲的部分地区进行了密集调查，但在伯利兹的调查较少，我们在 2015-2020 年的晚湿季和早干季期间在那里进行了研究。
我们使用装有已知吸引各种兰花蜂物种的化学物质的瓶式陷阱进行调查，这些陷阱在地理位置、历史年降水量、海拔和附近农业活动存在的地点进行。每个调查期间的每个样本都由相同数量的陷阱和相同的化学诱饵组成，它们的位置沿着样带随机排列。
在 86 个样本中，我们收集到了四个属的 24 个物种： （16 种）、 （3 种）、 （3 种）和 （2 种）。在我们最广泛的采样期间（2016 年 12 月至 2017 年 2 月），物种多样性与纬度、降水量或海拔无关；物种丰富度仅与降水量呈正相关。然而，典范对应分析表明，物种组成在所有三个环境梯度上都有所不同，像 、和 等物种在较干燥的北部最为常见，而 、和 等物种在较湿润的东南部更为常见。其他物种，如 、和 等，在整个采样区域都很常见。与远离农业区的地点相比，有农业活动的地点的平均物种多样性更高。Chao1 分析表明，在我们的地点可能还会发现其他物种，这一结论得到了来自相邻国家的记录的支持，也得到了我们经常通过对同一地点的重复调查，以及使用替代诱饵，来增加新物种的事实的支持。如果在我们迄今为止采样的月份/季节之外进行采样，可能会有更多的新物种出现。
