Foundation Species Abundance Influences Food Web Topology on Glass Sponge Reefs
Foundation species support communities across a wide range of ecosystems. Non-trophic interactions are considered the primary way foundation species influence communities, with their trophic interactions having little impact on community structure. Here we assess the relative trophic importance of a...
| Main Authors: | , , , , , , , , |
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2020-09-01
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| Series: | Frontiers in Marine Science |
| Subjects: | |
| Online Access: | https://www.frontiersin.org/article/10.3389/fmars.2020.549478/full |
| _version_ | 1818405082711982080 |
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| author | Stephanie K. Archer Stephanie K. Archer Amanda S. Kahn Amanda S. Kahn Mary Thiess Mary Thiess Lauren Law Sally P. Leys Sophia C. Johannessen Craig A. Layman Lily Burke Anya Dunham |
| author_facet | Stephanie K. Archer Stephanie K. Archer Amanda S. Kahn Amanda S. Kahn Mary Thiess Mary Thiess Lauren Law Sally P. Leys Sophia C. Johannessen Craig A. Layman Lily Burke Anya Dunham |
| author_sort | Stephanie K. Archer |
| collection | DOAJ |
| description | Foundation species support communities across a wide range of ecosystems. Non-trophic interactions are considered the primary way foundation species influence communities, with their trophic interactions having little impact on community structure. Here we assess the relative trophic importance of a foundation species and assess how its abundance can influence food web topology. Using empirical data and published trophic interactions we built food web models for 20 glass sponge reefs to examine how average live reef-building sponge abundance (proxied by percent cover) at the reef level is correlated with community structure and food web network topology. Then, using a generalized food web model and stable isotope data we examined the relative importance of sponges. Sponges were consumed by all species examined and contributed significantly to their diets. Additionally, sponges were the second most important node in our generalized reef food web. Several metrics of food web topology (connectance, clustering, and median degree) and community structure exhibited a threshold response to reef-building sponge cover, with the change point occurring between 8 and 13% live sponge cover. Below this threshold, as average sponge cover increases, the consumers observed on a reef rely on fewer sources and are consumed by fewer predators, resulting in food webs that are more clustered and less connected. Above the threshold, as average sponge cover increases, the reefs’ food webs are less clustered and more connected, with consumers utilizing more sources and having more predators. This corresponds with the finding that several generalist predators (e.g., rockfishes) are associated with high sponge cover reefs. Our results are not consistent with previous reports that increasing foundation species abundance decreases connectance in food webs. We propose that the influence of foundation species on food web topology may be dependent on palatability, and therefore relative trophic importance, of the foundation species. Finally, our findings have important implications for sponge reef conservation and management, as they suggest that reefs below the 10% sponge cover threshold support different communities than high live sponge cover reefs. |
| first_indexed | 2024-12-14T08:50:24Z |
| format | Article |
| id | doaj.art-e98e4c95400c4401b5d13858cf973d3c |
| institution | Directory Open Access Journal |
| issn | 2296-7745 |
| language | English |
| last_indexed | 2024-12-14T08:50:24Z |
| publishDate | 2020-09-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Marine Science |
| spelling | doaj.art-e98e4c95400c4401b5d13858cf973d3c2022-12-21T23:09:03ZengFrontiers Media S.A.Frontiers in Marine Science2296-77452020-09-01710.3389/fmars.2020.549478549478Foundation Species Abundance Influences Food Web Topology on Glass Sponge ReefsStephanie K. Archer0Stephanie K. Archer1Amanda S. Kahn2Amanda S. Kahn3Mary Thiess4Mary Thiess5Lauren Law6Sally P. Leys7Sophia C. Johannessen8Craig A. Layman9Lily Burke10Anya Dunham11Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, BC, CanadaLouisiana Universities Marine Consortium, Chauvin, LA, United StatesDepartment of Biological Sciences, University of Alberta, Edmonton, AB, CanadaMonterey Bay Aquarium Research Institute, Moss Landing, CA, United StatesPacific Biological Station, Fisheries and Oceans Canada, Nanaimo, BC, CanadaParks Canada, Peterborough, ON, CanadaDepartment of Biological Sciences, University of Alberta, Edmonton, AB, CanadaDepartment of Biological Sciences, University of Alberta, Edmonton, AB, CanadaInstitute of Ocean Sciences, Fisheries and Oceans Canada, Sidney, BC, CanadaDepartment of Applied Ecology, North Carolina State University, Raleigh, NC, United StatesInstitute of Ocean Sciences, Fisheries and Oceans Canada, Sidney, BC, CanadaPacific Biological Station, Fisheries and Oceans Canada, Nanaimo, BC, CanadaFoundation species support communities across a wide range of ecosystems. Non-trophic interactions are considered the primary way foundation species influence communities, with their trophic interactions having little impact on community structure. Here we assess the relative trophic importance of a foundation species and assess how its abundance can influence food web topology. Using empirical data and published trophic interactions we built food web models for 20 glass sponge reefs to examine how average live reef-building sponge abundance (proxied by percent cover) at the reef level is correlated with community structure and food web network topology. Then, using a generalized food web model and stable isotope data we examined the relative importance of sponges. Sponges were consumed by all species examined and contributed significantly to their diets. Additionally, sponges were the second most important node in our generalized reef food web. Several metrics of food web topology (connectance, clustering, and median degree) and community structure exhibited a threshold response to reef-building sponge cover, with the change point occurring between 8 and 13% live sponge cover. Below this threshold, as average sponge cover increases, the consumers observed on a reef rely on fewer sources and are consumed by fewer predators, resulting in food webs that are more clustered and less connected. Above the threshold, as average sponge cover increases, the reefs’ food webs are less clustered and more connected, with consumers utilizing more sources and having more predators. This corresponds with the finding that several generalist predators (e.g., rockfishes) are associated with high sponge cover reefs. Our results are not consistent with previous reports that increasing foundation species abundance decreases connectance in food webs. We propose that the influence of foundation species on food web topology may be dependent on palatability, and therefore relative trophic importance, of the foundation species. Finally, our findings have important implications for sponge reef conservation and management, as they suggest that reefs below the 10% sponge cover threshold support different communities than high live sponge cover reefs.https://www.frontiersin.org/article/10.3389/fmars.2020.549478/fullcommunity structurefacilitationfood websnetworksporiferaspecies interactions |
| spellingShingle | Stephanie K. Archer Stephanie K. Archer Amanda S. Kahn Amanda S. Kahn Mary Thiess Mary Thiess Lauren Law Sally P. Leys Sophia C. Johannessen Craig A. Layman Lily Burke Anya Dunham Foundation Species Abundance Influences Food Web Topology on Glass Sponge Reefs Frontiers in Marine Science community structure facilitation food webs networks porifera species interactions |
| title | Foundation Species Abundance Influences Food Web Topology on Glass Sponge Reefs |
| title_full | Foundation Species Abundance Influences Food Web Topology on Glass Sponge Reefs |
| title_fullStr | Foundation Species Abundance Influences Food Web Topology on Glass Sponge Reefs |
| title_full_unstemmed | Foundation Species Abundance Influences Food Web Topology on Glass Sponge Reefs |
| title_short | Foundation Species Abundance Influences Food Web Topology on Glass Sponge Reefs |
| title_sort | foundation species abundance influences food web topology on glass sponge reefs |
| topic | community structure facilitation food webs networks porifera species interactions |
| url | https://www.frontiersin.org/article/10.3389/fmars.2020.549478/full |
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