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Abstract Disturbances are increasing in size and frequency with climate change, facilitating species that opportunistically exploit areas where habitat‐forming foundation species have been removed. Although it is well‐recognized that consumers, disease and weedy space‐holders can affect foundation species’ resistance to and recovery from disturbance, how predators influence their resilience is less clear.In salt marshareas de‐vegetated by drought and intensive snailLittoraria irroratagrazing (hereafter, ‘die‐offs’), we monitored bird use and experimentally manipulated bird and nekton access to the vegetated borders of die‐off mudflats across periods of both vegetation die‐off and regrowth to explore how these predators mediate the resilience of cordgrassSpartina alterniflora, the foundation species that structures US Atlantic coast salt marshes.Surveys revealed that birds, especially probers that agitate soils, forage year‐round for invertebrates in die‐off mudflats in our study area but not in adjacent vegetated areas.During periods of die‐off, cordgrass borders accessible to bird and nekton predators retreated >3‐times slower and snail densities were halved, relative to predator exclusion cages. In predator‐accessible plots, slower border retreat corresponded to greater snail infection by a bird host‐dependent trematode parasite. During recovery, cordgrass borders revegetated more quickly, and snail densities declined faster over time in unmanipulated controls relative to predator exclusions.Synthesis. These findings suggest that birds, through their transmission of parasites to snails, appear to act synergistically with snail‐consuming nekton to slow cordgrass loss after drought‐snail disturbances. Predator access also corresponds to faster cordgrass recovery as environmental conditions improve, although the mechanisms behind this need further investigation. Thus, predators that opportunistically forage within disturbances have the potential to suppress consumer impacts through multiple mechanisms, including consumption and disease transmission, thereby bolstering foundation species’ resilience and modulating whole ecosystem responses to climate change.
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Birds are not the only ones impacted by guidance to cease bird feeding
Abstract Humans have a particularly strong connection with birds, driving the enormous popularity of residential bird feeding in much of the world.We conducted a web search to document US state wildlife management agency responses to two recent avian disease outbreaks, finding that 23 agencies made recommendations to cease feeding wild birds in 2021–2022.The psychological benefits of bird feeding for humans are well‐documented but often overlooked in management decisions in response to avian disease outbreaks.Likewise, ecological evidence does not necessarily support ceasing bird feeding to reduce the spread of every avian disease.Ecological and social science need to be applied in tandem to ensure that well‐intended guidance to cease feeding of birds does not have unintended consequences.
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- Award ID(s):
- 2206057
- PAR ID:
- 10478670
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- People and Nature
- Volume:
- 6
- Issue:
- 1
- ISSN:
- 2575-8314
- Format(s):
- Medium: X Size: p. 20-26
- Size(s):
- p. 20-26
- Sponsoring Org:
- National Science Foundation
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