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Abstract Supplemental feeding can increase the overall health of animals but also can have variable effects on how animals defend themselves against parasites. However, the spatiotemporal effects of food supplementation on host–parasite interactions remain poorly understood, likely because large‐scale, coordinated efforts to investigate them are difficult.Here, we introduce the Nest Parasite Community Science Project, which is a community‐based science project that coordinates studies with bird nest box ‘stewards’ from the public and scientific community. This project was established to understand broad ecological patterns between hosts and their parasites.The goal of this study was to determine the effect of food supplementation on eastern bluebirds (Sialia sialis) and their nest parasite community across the geographic range of the bluebirds from 2018 to 2021. We received 674 nests from 69 stewards in 26 states in the eastern United States. Nest box stewards reported whether or not they provided mealworms or suet near nesting bluebirds, then they followed the nesting success of the birds (number of eggs laid and hatched, proportion that hatched, number and proportion of nestlings that successfully fledged). We then identified and quantified parasites in the nests.Overall, we found that food supplementation increased fledging success. The most common nest parasite taxon was the parasitic blow fly (Protocalliphora sialia), but a few nests contained fleas (Ceratophyllus idius,C. gallinaeandOrchopeas leucopus) and mites (Dermanyssusspp. andOrnithonyssusspp.). Blow flies were primarily found at northern latitudes, where food supplementation affected blow fly prevalence. However, the direction of this effect varied substantially in direction and magnitude across years. More stewards fed bluebirds at southern latitudes than at northern latitudes, which contradicts the findings of other community‐based science projects.Overall, food supplementation of birds was associated with increased host fitness but did not appear to play a consistent role in defence against these parasites across all years. Our study demonstrates the importance of coordinated studies across years and locations to understand the effects of environmental heterogeneity, including human‐based food supplementation, on host–parasite dynamics.
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Host-parasite interactions between Xenoglossa pruinosa (Apidae: Eucerini) and Triepeolus remigatus (Apidae: Epeolini) are characterized by tolerance and avoidance
Abstract In cleptoparasitic bees, host aggression and detection avoidance might be the main selective pressures shaping host-parasite interactions. However, the behavioral responses toward parasitism are unknown for most host species. In this study, we investigated the host-parasite interactions and behaviors of the cleptoparasitic beeTriepeolus remigatuswhen parasitizing the nests of its host, the squash beeXenoglossa(Peponapis)pruinosa. Using circle-tube behavioral assays and direct observations at a nest aggregation ofX. pruinosa, we assessed whether interactions between host and parasite were aggressive, tolerant, or avoidant and characterized the general parasitic behavior ofT. remigatus. Our results reveal a lack of aggression between host and cuckoo bees, with interactions primarily characterized by tolerant and avoidant behaviors. Squash bees displayed minimal aggression toward both conspecifics and parasites. Interestingly, despite the absence of aggressive responses,T. remigatuspreferred entering nests while the host was foraging, potentially indicating a strategy to avoid the discovery of parasitic visits. Furthermore, field observations provided insights into the parasitic behavior ofT. remigatus, revealing primarily rapid visits to host nests without extensive inspection. The limited aggression and short time for nest visits observed inT. remigatussuggest adaptations to optimize parasitic success while minimizing host detection. Overall, our findings contribute to a better understanding of the behavior of open-cell parasites and provide a first accounting of the squash bee behavior when encountering parasitic bees. Further research is needed to elucidate the mechanisms underlying host-parasite coevolution and response to parasitism in ground-nesting bees.
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- Award ID(s):
- 2046474
- PAR ID:
- 10584568
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Apidologie
- Volume:
- 55
- Issue:
- 6
- ISSN:
- 0044-8435
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1007/s13592-024-01121-4
