Wildlife ecotourism can offer a source of revenue which benefits local development and conservation simultaneously. However, habituation of wildlife for ecotourism can cause long-term elevation of glucocorticoid hormones, which may suppress immune function and increase an animal’s vulnerability to disease. We have previously shown that western lowland gorillas (Gorilla gorilla gorilla) undergoing habituation in Dzanga-Sangha Protected Areas, Central African Republic, have higher fecal glucocorticoid metabolite (FGCM) levels than both habituated and unhabituated gorillas. Here, we tested the relationship between FGCM levels and strongylid infections in the same gorillas. If high FGCM levels suppress the immune system, we predicted that FGCM levels will be positively associated with strongylid egg counts and that gorillas undergoing habituation will have the highest strongylid egg counts, relative to both habituated and unhabituated gorillas. We collected fecal samples over 12 months in two habituated gorilla groups, one group undergoing habituation and completely unhabituated gorillas. We established FGCM levels and fecal egg counts of Necator/Oesophagostomum spp. and Mammomonogamus sp. Controlling for seasonal variation and age-sex category in strongylid infections we found no significant relationship between FGCMs and Nectator/Oesophagostomum spp. or Mammomonogamus sp. egg counts in a within group comparison in either a habituated group or a group undergoing habituation. However, across groups, egg counts of Nectator/Oesophagostomum spp. were lowest in unhabituated animals and highest in the group undergoing habituation, matching the differences in FGCM levels among these gorilla groups. Our findings partially support the hypothesis that elevated glucocorticoids reduce a host’s ability to control the extent of parasitic infections, and show the importance of non-invasive monitoring of endocrine function and parasite infection in individuals exposed to human pressure including habituation process and ecotourism.

野生动物生态旅游可以提供收入来源，同时有利于当地的发展和保护。然而，野生动物对生态旅游的习惯会导致糖皮质激素长期升高，这可能会抑制免疫功能并增加动物对疾病的脆弱性。我们之前已经证明了西部低地大猩猩（Gorilla gorilla gorilla) 在中非共和国 Dzanga-Sangha 保护区进行习惯化的大猩猩的粪便糖皮质激素代谢物 (FGCM) 水平高于习惯化和非习惯化的大猩猩。在这里，我们测试了同一只大猩猩的 FGCM 水平与圆线虫感染之间的关系。如果高 FGCM 水平抑制免疫系统，我们预测 FGCM 水平将与圆线虫卵计数呈正相关，并且相对于习惯化和未习惯化的大猩猩，经历习惯化的大猩猩将具有最高的圆线虫卵计数。我们在两个习惯化的大猩猩组中收集了超过 12 个月的粪便样本，一组正在习惯化和完全不习惯化的大猩猩。我们建立了Necator / Oesophagostomum的 FGCM 水平和粪卵计数spp. 和Mammomonogamus sp。控制圆线虫感染中的季节性变化和年龄-性别类别，我们发现 FGCM 与Nectator/Oesophagostomum spp之间没有显着关系。或Mammomonogamus sp。在习惯组或正在接受习惯的组中进行组内比较中的卵子计数。然而，在各组中，Nectator/Oesophagostomum的卵计数spp. 在不习惯的动物中最低，在适应的组中最高，与这些大猩猩组之间的 FGCM 水平差异相匹配。我们的研究结果部分支持了这样的假设，即糖皮质激素升高会降低宿主控制寄生虫感染程度的能力，并表明非侵入性监测暴露于人类压力（包括习惯过程和生态旅游）的个体的内分泌功能和寄生虫感染的重要性。