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Invasive marine invertebrates are increasingly recognized as a potential disturbance to coastal ecosystems. We sought to better document the taxonomic composition of subtidal communities around Long Island to obtain a baseline that can be used to monitor current and future invasions of non-indigenous species. We placed settlement blocks at 18 sites along the coast of Long Island, New York, for three months. After recovering blocks at 12 sites, we analyzed the taxonomic composition of fouling communities on the blocks. We observed 64 invertebrate and 3 algal taxa, with large variation in taxon richness among sites. Multivariate analyses revealed that although taxon composition was significantly dissimilar between north and south shores, variation in dissimilarity did not differ significantly between shores. The high variability in taxon composition observed among sites indicates that additional research is needed to expand our knowledge of invertebrate diversity in the waters surrounding Long Island. Adding more sites and replicate blocks within sites could improve future sampling designs. This research will benefit continuing efforts to monitor, manage, and prevent the establishment of marine invasive species.
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A decade of invertebrate recruitment at Santa Catalina Island, California
Marine fouling communities have long provided model systems for studying the ecology of community development, and settlement plates are the tool of choice for this purpose. Decades of plate deployments provide a baseline against which present-day trends can be interpreted, with one classic trend being the ultimate dominance of plates by colonial and encrusting taxa. Here we report the results of annual deployments of settlement plates from 2010 to 2021 in the shallow sub-tidal of southern California, where the recruitment of invertebrates and algae was recorded photographically, and resolved to functional group (solitary, encrusting, and arborescent) and the lowest taxon possible. The communities on these plates differed among years, with trends in abundances varying by functional group and taxon; solitary taxa consistently were abundant, but encrusting taxa declined in abundance. Seawater temperature and the subsurface concentration of chlorophyll a differed among years, and there was a weak inverse association between temperature and the abundances of encrusting taxa. Long-term increases in seawater temperature therefore could serve as a mechanism causing fouling communities to change. Because of the prominence of encrusting taxa in fouling communities, the shifts in abundance of this functional group reported here may portend ecologically significant changes in fouling communities exposed to warmer seawater because of an alleviation of competition for a classically limiting resource ( i.e ., space).
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- Award ID(s):
- 2019992
- PAR ID:
- 10428117
- Date Published:
- Journal Name:
- PeerJ
- Volume:
- 10
- ISSN:
- 2167-8359
- Page Range / eLocation ID:
- e14286
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract The supply of propagules mediates recruitment and population dynamics, thereby driving community resilience following disturbances. These relationships are of interest on tropical reefs, where coral populations have drastically declined in abundance and sexual recruitment is the only means by which they will recover. To better understand the causes and implications of variation in this vital rate (i.e., recruitment), coral recruitment was measured in Mo'orea, French Polynesia, and St. John, U.S. Virgin Islands, using settlement tiles deployed from 2005 to 2019. The results were used to test two hypotheses: (1) annual variation in recruitment is a weak predictor of long‐term variation in recruitment, but (2) it is associated with seawater temperature. Coral recruitment varied over space and time, so that differences in recruitment between consecutive years were uninformative of long‐term trends. Recruitment varied among years in an apparently chaotic manner, but the variation reflected linear and quadratic associations with mean annual temperature and the daily variation in temperature. These associations are consistent with theory addressing the mechanisms by which temperature affects coral larvae and recruitment. Comprehension of these mechanisms is required to accurately interpret evidence of coral recruitment collapse, and to elucidate the conditions favoring recovery of coral communities through recruitment.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.7717/peerj.14286
