Roubik D W, Ackerman J D
Smithsonian Tropical Research Institute, APDO 2072, Balboa, Panama.
APO, 34002-0011, Miami, FL, USA.
Oecologia. 1987 Sep;73(3):321-333. doi: 10.1007/BF00385247.
Abundance patterns during 6-7 years and orchid visitation were determined for 51 species of the 57 local euglossine bees. Male bees were counted at 3 chemical attractants presented in the same manner each month. Sites were separated by 75 km but included wet Atlantic forest at 500 m elevation, moist forest at 180 m near Barro Colorado Island, and cloud forest at 900 m near the Pacific ocean. 1. From 15 to 30 euglossine species of 4 genera were active in each month and site; monthly species number and general bee abundance were positively correlated. Many species had 3 annual abundance peaks (range 1-4) and were active throughout the year, but peak annual abundances rarely occurred during late wet or early dry seasons. In contrast, Eufriesea generally were present as adults only 1-2 months in a year. 2. Euglossine populations were exceptionally stable. Species at each site were more stable than any known insect population, and stability and abundance were positively associated. However, year-to-year population stability and the degree of seasonality were not correlated. Among the three sites, the more diverse (species rich) bee assemblages displayed lower stability; these were the wetter and upland sites. 3. The most abundant bees visited more orchid species. Eg. and El. each visited and average of 4 orchid species (range 0-13); Ex. and Ef. visited 0-3. Stable populations did not visit more or fewer orchid species than did unstable populations. 4. Less than 68% of species at each site visited orchid flowers; less than a few dozen of the 100-800 bees counted in a day carried orchid pollinaria. Over 20% of the euglossine species never were seen with pollinaria at any site and probably seldom visit orchids in central Panama. 5. Most bee species visited 1 or no fragrance orchids in a given habitat. Orchids tended to utilize common pollinators that seldom included more than 1 species, and they utilized stable or unstable, seasonal or aseasonal bees. However, the most stable and abundant bee, Eg. imperialis, rarely pollinated orchids; fewer than 10 of ca. 20000 bees carried pollinaria. 6. Orchids may interact primarily with discrete seasonal bee population peaks-probably the emerging adults. Although specialized orchid preferences are implicated for species that visit few or no local orchids but pollinate other species and carry pollinaria in other areas, euglossine bees do not need orchids to survive or reproduce.
我们确定了57种当地 Euglossine 蜜蜂中51种蜜蜂在6 - 7年期间的数量模式和兰花访花情况。每月以相同方式在3种化学引诱剂处统计雄蜂数量。各地点相距75公里，包括海拔500米的湿润大西洋森林、靠近巴罗科罗拉多岛海拔180米的潮湿森林以及靠近太平洋海拔900米的云雾森林。1. 每个月和每个地点有4个属的15至30种 Euglossine 蜜蜂活跃；月物种数量与蜜蜂总数量呈正相关。许多物种有3个年度数量峰值（范围为1 - 4个）且全年活跃，但年度数量峰值很少出现在雨季后期或旱季早期。相比之下，Eufriesea 属的蜜蜂通常一年中仅作为成虫出现1 - 2个月。2. Euglossine 蜜蜂种群异常稳定。每个地点的物种比任何已知昆虫种群都更稳定，且稳定性与数量呈正相关。然而，年际种群稳定性与季节性程度并无关联。在这三个地点中，蜜蜂群落多样性越高（物种越丰富）稳定性越低；这些是更湿润的高地地点。3. 数量最多的蜜蜂访问的兰花物种更多。例如，Eg. 和 El. 平均各访问4种兰花物种（范围为0 - 13种）；Ex. 和 Ef. 访问0 - 3种。稳定种群访问的兰花物种数量并不比不稳定种群多或少。4. 每个地点不到68%的物种访问兰花花朵；一天中统计的100 - 800只蜜蜂中，携带兰花花粉块的不到几十只。超过20%的 Euglossine 物种在任何地点都从未被观察到携带花粉块，可能很少访问巴拿马中部的兰花。5. 在特定栖息地，大多数蜜蜂物种访问1种或不访问有香味的兰花。兰花倾向于利用常见传粉者，这些传粉者很少包含超过1个物种，并且它们利用稳定或不稳定、季节性或非季节性的蜜蜂。然而，最稳定且数量最多的蜜蜂，即 Eg. imperialis，很少为兰花授粉；在约20000只蜜蜂中，携带花粉块的不到10只。6. 兰花可能主要与离散的季节性蜜蜂种群峰值相互作用——可能是刚羽化的成虫。尽管对于那些很少或不访问当地兰花但为其他物种授粉且在其他地区携带花粉块的物种存在专门的兰花偏好，但 Euglossine 蜜蜂不需要兰花来生存或繁殖。
