Captive propagation can lead to phenotypic change in fish populations, but the broader community‐level consequences of captive phenotypes remain largely unknown. We investigate the degree to which captive propagation alters the phenotypes and ecological roles of fish stocked into wild communities. We focus on captive propagation of western mosquitofish ( Captive propagation in mosquitofish consistently generated novel mixtures of morphological and behavioural traits that deviate from those of wild populations. A mesocosm experiment showed that mosquitofish from captive propagation facilities differ from wild fish in their effects on aquatic community structure by shifting their consumption to less‐mobile, benthic prey.
Evaluating fish feeding behaviours is imperative to understanding prey resource use in the field. Previous work on fish feeding has taken place almost exclusively in a laboratory setting, which may impose artificial restrictions. Thus, we aimed to evaluate the constraints the captive setting places on fish feeding behaviours. We recorded polymorphic (littoral and pelagic) bluegill sunfish ( Gape velocity, ram velocity, and body deceleration were higher in the field than in captive fish. Significantly greater gape velocity in field fish suggests that these fish feed with greater suction pressure than captive fish. Prey effects were detected, as brine shrimp feeding events were characterised by slower gape and ram velocities and a smaller gape. Feeding events on brine shrimp in the field were similar to feeding events on worms in the laboratory suggesting an artefact of training. These results indicate that feeding behaviours measured in the laboratory may not be representative of feeding behaviours in the wild. Further consideration of organismal performance and laboratory constraints should be taken in future functional studies.
- PAR ID:
- 10459294
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Freshwater Biology
- Volume:
- 64
- Issue:
- 5
- ISSN:
- 0046-5070
- Page Range / eLocation ID:
- p. 926-932
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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