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ABSTRACT We observed a novel, nocturnal cleaning interaction between a cleaner shrimp (GenusUrocaridella) and the giant moray eel (Gymnothorax javanicus) on a lagoonal patch reef in Moorea, French Polynesia. Over the course of an 85‐min foraging bout (recorded on video by a snorkeler), we observed three separate, stereotyped cleaning interactions betweenG. javanicusand a cleaner shrimp in the genus Urocaridella (which surveys of Moorea biodiversity previously visually identified asUrocaridella antonbruunii). During these interactions, the shrimp would slowly crawl along one of the eel's flanks towards its head, enter its mouth, emerge on the other side of its head, then crawl back towards the reef along the eel's opposite flank, often causing it to jolt in response. On each of the visits, the moray spent roughly 9–12 min at the cleaning station and was observed being cleaned for a total of 62 s. Although this was a chance observation of only a few instances of cleaning, it may have several important implications for our understanding of the behavioral ecology of cleaning mutualisms, including (1) indicating potential temporal trade‐offs between being cleaned and foraging in eels, (2) suggesting a degree of temporal niche partitioning among sympatric cleaner species and (3) updating our understanding of cleaner‐client communication, given the nocturnal nature of our observations.
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This content will become publicly available on March 1, 2026
Comparing remote and hand‐held video observation methods for quantifying a cleaning mutualism
Abstract Field studies of cleaning mutualisms use a variety of methods to quantify behavioral dynamics. Studies in marine systems typically utilize data recorded by human observers on scuba or snorkel or via remote underwater video. The effects of these different methods on cleaner–client behaviors have not been rigorously assessed. We quantified cleaner–client interactions at 13 bluestreak cleaner wrasse (Labroides dimidiatus) cleaning stations in Moorea, French Polynesia using hand‐held and remote videos. We found that cleaning, cheating, and client posing rates, cleaning duration, and client species richness were all greater in the remote than in the hand‐held videos, suggesting that human presence disrupts cleaning interactions by inducing antipredator responses among clients. Some metrics, such as the ratio of cleaner chasing to cleaning behavior and the cleaners' benthic feeding rate, were higher for the hand‐held than the remote videos, possibly due to limited access of cleaners to clients in the presence of humans. Other metrics, such as cleaner and client chasing rates, the ratio of cleaning to cheating behaviors, and the duration of cleaner chases, did not differ between video types. Finally, piscivorous clients were far more abundant in the remote than the hand‐held videos, suggesting that piscivores are particularly sensitive to human presence, likely because they are targeted by fishers. Overall, our study suggests that human presence can bias studies of cleaning behavior and cleaner–client interactions, and that remote cameras should be used to conduct behavioral studies. These potential biases should be considered when interpreting existing behavioral data.
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- PAR ID:
- 10591139
- Publisher / Repository:
- J. Fish Biology
- Date Published:
- Journal Name:
- Journal of Fish Biology
- Volume:
- 106
- Issue:
- 3
- ISSN:
- 0022-1112
- Page Range / eLocation ID:
- 775 to 783
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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