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7. Grazers and predators mediate the post-settlement bottleneck in Caribbean octocoral forests.

Author

Wells, Christopher D., Benz, Joseph, Tonra, Kaitlyn J., Anderson, Emily R., and Lasker, Howard R.

Subjects
CORALS, OCTOCORALLIA, SCLERACTINIA, PREDATORY animals, CORAL reefs & islands, CORAL declines
Abstract

In the Caribbean, reef-building scleractinian corals have declined precipitously and octocorals have emerged as one of their main successors. The success of octocorals and the formation of octocoral forests has been attributed to their continuing recruitment to reef habitats, as well as tolerance to pollution, reduced direct competition with scleractinians, and resistance and resilience to climatic events. Benthic grazers on coral reefs can facilitate the growth and recruitment of corals by reducing the abundance of competitive algal turfs and macroalgae. However, grazing can also hinder corals through sublethal damage to coral tissue and predation of recruits. We assessed the effects of grazing by fishes and the sea urchin Diadema antillarum as well as predation by mesofauna on octocoral recruitment through a series of manipulative in situ and ex situ experiments. Exposure to fish and urchin grazing significantly reduced the post-settlement survival of octocoral recruits, while turf-associated mesofauna did not significantly affect recruitment. We also found a positive relationship between octocoral recruitment and the abundance of turf algae, which may reflect the deleterious effect of grazing on both turf algae and octocoral recruits. These data suggest that grazers and predators mediate the bottleneck characteristic of recruitment, primarily through their effect on post-settlement survival. Thus, the declines in the abundance of grazing fishes and urchins throughout the Caribbean may have contributed to the increase in Caribbean octocoral abundance, concurrent with the loss of scleractinians. [ABSTRACT FROM AUTHOR]

Published
2024
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14. Octocorals, scleractinia, macroalgae surveys describing species abundance and distribution on St. John and St. Thomas, USVI in 2011 (St. John LTREB project, VI Octocorals project)

Author

Edmunds, Peter J., Lasker, Howard, Tsounis, Georgios, Edmunds, Peter J., Lasker, Howard, and Tsounis, Georgios

Abstract

Dataset: octocoral - sp. abundance and distribution, Octocorals, scleractinia, macroalgae surveys describing species abundance and distribution on St. John and St. Thomas, USVI in 2011 (St. John LTREB project, VI Octocorals project) For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/630404, NSF Division of Ocean Sciences (NSF OCE) OCE-1332915, NSF Division of Ocean Sciences (NSF OCE) OCE-1334052, NSF Division of Environmental Biology (NSF DEB) DEB-1350146

Published
2023

17. Boundaries and hybridization in a secondary contact zone between freshwater mussel species (Family:Unionidae)

Author

Porto-Hannes, Isabel, Burlakova, Lyubov E., Zanatta, David T., and Lasker, Howard R.

Abstract

Correct species identification and delineation are crucial for effective conservation and management. However, species delineation can be problematic in the presence of morphological ambiguities due to phenotypic plasticity, convergence, and/or interspecific hybridization. Here, we investigated the degree of hybridization between two closely related freshwater mussel species [Bivalvia: Unionidae; Lampsilis siliquoidea(Barnes) and L. radiata(Gmelin)] that present intermediate forms in areas of sympatry. Unionids have a distinct form of mitochondrial DNA (mtDNA) inheritance, termed doubly uniparental inheritance (DUI) where female mtDNA (F-type) is transmitted to all progeny but male mtDNA (M-type) is mostly inherited by the males resulting in mostly homoplasmic females and heteroplasmic males. An individual was identified as hybrid when F-type and M-type mtDNA of the two different species were found in the same individual. Twelve out of 116 sequenced males were identified as hybrids indicating that these species hybridize where their geographic range overlaps in the lower Great Lakes and St. Lawrence basins. Microsatellite analyses further support the occurrence of hybridization but at a larger spatial scale than indicated by the mitochondrial analyses. We also found that strong within-species population genetic structure affects the detection of purebred individuals overestimating the number of hybrids. Given the large geographic scale and proportion of hybrids found in this study, natural hybridization and introgression need to be considered when implementing local biodiversity inventories, identifying waterbodies as source of organisms for relocation and restoration projects and when setting appropriate conservation policies.

Published
2024
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18. Three‐dimensional species distribution modelling reveals the realized spatial niche for coral recruitment on contemporary Caribbean reefs.

Author

Martínez‐Quintana, Ángela, Lasker, Howard R., and Wilson, Adam M.

Subjects
*CORALS, *REEFS, *SPECIES distribution, *CORAL reefs & islands, *SCLERACTINIA, *CORAL declines, *OCTOCORALLIA, *ALCYONACEA
Abstract

The three‐dimensional structure of habitats is a critical component of species' niches driving coexistence in species‐rich ecosystems. However, its influence on structuring and partitioning recruitment niches has not been widely addressed. We developed a new method to combine species distribution modelling and structure from motion, and characterized three‐dimensional recruitment niches of two ecosystem engineers on Caribbean coral reefs, scleractinian corals and gorgonians. Fine‐scale roughness was the most important predictor of suitable habitat for both taxa, and their niches largely overlapped, primarily due to scleractinians' broader niche breadth. Crevices and holes at mm scales on calcareous rock with low coral cover were more suitable for octocorals than for scleractinian recruits, suggesting that the decline in scleractinian corals is facilitating the recruitment of octocorals on contemporary Caribbean reefs. However, the relative abundances of the taxa were independent of the amount of suitable habitat on the reef, emphasizing that niche processes alone do not predict recruitment rates. [ABSTRACT FROM AUTHOR]

Published
2023
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26. Antillogorgia elisabethae branch extension measurements for clipped and unclipped colonies from San Salvador and Abaco, The Bahamas in June 1999 and June 2000

Author

Lasker, Howard and Lasker, Howard

Abstract

Dataset: Coral Growth, This dataset represents Antillogorgia elisabethae branch extension measurements for colonies clipped to 10 or 4 branches or not clipped. Data were collected as part of a project on recruitment among density-manipulated populations of Caribbean gorgonians sampled from San Salvador and Abaco, The Bahamas from June 1999 and June 2000. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/872600, NSF Division of Ocean Sciences (NSF OCE) OCE-1756381, NSF Division of Ocean Sciences (NSF OCE) OCE-0327129

Published
2022

27. Antillogorgia elisabethae clipping experiment in San Salvador and Abaco, The Bahamas from June 1999 and June 2000

Author

Lasker, Howard and Lasker, Howard

Abstract

Dataset: Coral Branching per Source, This dataset represents Antillogorgia elisabethae colony growth measurements for colonies clipped to 10 or 4 branches or not clipped in June 1999 and monitored in June 2000 at two sites in The Bahamas. This dataset includes branching data including per capita branching ratio, number of new branches, and number of new branches per mother branch. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/872486, NSF Division of Ocean Sciences (NSF OCE) OCE-1756381, NSF Division of Ocean Sciences (NSF OCE) OCE-0327129

Published
2022

32. Variability of size structure and species composition in Caribbean octocoral communities under contrasting environmental conditions

Author

Tsounis, Georgios, Edmunds, Peter J., Bramanti, Lorenzo, Gambrel, Bonnie, and Lasker, Howard R.

Subjects
Reefs, Coral reef ecosystems -- Observations, Environmental quality, Niches (Ecology), Octocorals -- Observations, Biological sciences
Abstract

Octocorals have increased in abundance on a number of Caribbean reefs, but this trend has largely been reported with functional group or genus resolution. A species-level analysis of octocoral communities in St. John, US Virgin Islands was conducted to better understand how this taxon will respond to changing conditions based on their synecology at two sites that are 1.5 km apart and differ in physical conditions. East Cabritte is characterized by moderate wave energy, low sedimentation, and clear water, while contrasting conditions characterize Europa Bay. Surveys conducted in 2014 and 2015 showed that the abundance and size of adult octocorals differed between sites, with taller and denser communities at East Cabritte than Europa Bay (mean height of 32 versus 20 cm; 18 versus 8 colonies m.sup.-2). Octocoral diversity and evenness were similar between sites, although multivariate octocoral community structure differed between sites regardless of whether octocorals were resolved to genera or species. Genus-resolution masked differences between sites for speciose genera like Eunicea. The broad overlap in species representation at both sites suggests that diversity is less responsive than community structure to differing environmental conditions, perhaps because the ecological niches of these species are broad. With 35 octocoral species, and diversity and abundances comparable to those studied > 40 years ago on shallow Caribbean reefs, the dense octocoral communities appearing on some present-day reefs reflect expanded benthic occupancy by a well-known (rather than a novel) community type., Author(s): Georgios Tsounis [sup.1] , Peter J. Edmunds [sup.1] , Lorenzo Bramanti [sup.2] , Bonnie Gambrel [sup.3] , Howard R. Lasker [sup.3] Author Affiliations: (1) California State University Northridge, 0000 [...]

Published
2018
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33. Percent cover of living organisms on experimental tiles with different levels of turf algae cover during an in-situ experiment in St. John, US Virgin Islands in August and September of 2019

Author

Wells, Christopher, Martinez-Quintana, Angela, Tonra, Kaitlyn, Lasker, Howard, Wells, Christopher, Martinez-Quintana, Angela, Tonra, Kaitlyn, and Lasker, Howard

Abstract

Dataset: Turf Tile Cover, Percent cover of living organisms on experimental tiles of three treatments (scrubbed, reef, protected) determined using digital images of each tile taken on days 0, 19, and 57 after field deployment. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/855879, NSF Division of Ocean Sciences (NSF OCE) OCE-1756381

Published
2021

34. Coral reef abundance on shallow reefs of St. John, US Virgin Islands, 1992-2014

Author

Edmunds, Peter J., Lasker, Howard, Edmunds, Peter J., and Lasker, Howard

Abstract

Dataset: MEPS Edmunds Lasker Fig 2, Coral reef abundance on shallow reefs of St. John, US Virgin Islands, 1992-2014. Benthic coral reef communities were monitored on the south shore of St. John. In 1992, six sites were selected using random coordinates constrained to hard bottom on fringing reefs (< 9-m depth) between Cabritte Horn and White Point, and were permanently marked. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/750513, NSF Division of Environmental Biology (NSF DEB) DEB-0841441, NSF Division of Ocean Sciences (NSF OCE) OCE-1332915, NSF Division of Environmental Biology (NSF DEB) DEB-1350146

Published
2021

35. Polyp settlement and polyp counts on experimental tiles with different levels of turf algae cover during an in-situ experiment in St. John, US Virgin Islands in August and September of 2019.

Author

Wells, Christopher, Martinez-Quintana, Angela, Tonra, Kaitlyn, Lasker, Howard, Wells, Christopher, Martinez-Quintana, Angela, Tonra, Kaitlyn, and Lasker, Howard

Abstract

Dataset: Turf Polyp Counts, Polyp settlement and polyp counts on experimental tiles with different levels of turf algae cover (low: “scrubbed”; medium: “reef”; high: “protected”) up to 57 days after settlement. The in-situ experiment took place in Grootpan Bay, St. John, US Virgin Islands between August 3rd to September 9th, 2019. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/855867, NSF Division of Ocean Sciences (NSF OCE) OCE-1756381

Published
2021

36. Octocoral recruitment surveys on transects at 5 sites on the south shore of St. John, US Virgin Islands, 2014-2019.

Author

Lasker, Howard and Lasker, Howard

Abstract

Dataset: Octocoral Recruitment, This dataset includes species identifications and sizes from octocoral recruitment surveys conducted on transects at five sites on the south shore of St. John, US Virgin Islands from 2014-2019. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/851382, NSF Division of Ocean Sciences (NSF OCE) OCE-1334052, NSF Division of Ocean Sciences (NSF OCE) OCE-1756381

Published
2021

37. Locations of mapped polyps on experimental tiles with different levels of turf algae cover during an in-situ experiment in St. John, US Virgin Islands in August and September of 2019

Author

Wells, Christopher, Martinez-Quintana, Angela, Tonra, Kaitlyn, Lasker, Howard, Wells, Christopher, Martinez-Quintana, Angela, Tonra, Kaitlyn, and Lasker, Howard

Abstract

Dataset: Turf Polyp Locations, Locations of mapped polyps on experimental tiles of three treatments (scrubbed, reef, protected). For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/855889, NSF Division of Ocean Sciences (NSF OCE) OCE-1756381

Published
2021

38. Cell counts for 11 P. homomalla embryos taken every 5-10 minutes from fertilization to 13 hours after fertilization from adult corals collected in Round Bay, St. John, USVI in July of 2019

Author

Tonra, Kaitlyn, Wells, Christopher, Lasker, Howard, Tonra, Kaitlyn, Wells, Christopher, and Lasker, Howard

Abstract

Dataset: P. homomalla development (fine), Cell counts for 11 Plexaura homomalla embryos taken every 5-10 minutes from fertilization to 13 hours after fertilization. Adult corals used in this study were collected in Round Bay, St. John, USVI on July 14–15, 2019. The results publication for this dataset is Tonra et al. (2021, see Fig. 3). For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/855801, NSF Division of Ocean Sciences (NSF OCE) OCE-1756381

Published
2021

39. Counts of individuals and cell division for 100 Plexaura homomalla embryos from fertilization to 24 hours after fertilization from adult corals collected in Round Bay, St. John, USVI in July of 2019

Author

Tonra, Kaitlyn, Wells, Christopher, Lasker, Howard, Tonra, Kaitlyn, Wells, Christopher, and Lasker, Howard

Abstract

Dataset: P. homomalla development (coarse), Counts of individuals and cell division for 100 Plexaura homomalla embryos from fertilization to 24 hours after fertilization. Adult corals used in this study were collected in Round Bay, St. John, USVI on July 14–15, 2019. The results publication for this dataset is Tonra et al. (2021, see Fig. 4). For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/855766, NSF Division of Ocean Sciences (NSF OCE) OCE-1756381

Published
2021

40. Coral reef community structure on shallow reefs of St. John, US Virgin Islands, 1992-2014

Author

Edmunds, Peter J., Lasker, Howard, Edmunds, Peter J., and Lasker, Howard

Abstract

Dataset: MEPS Edmunds Lasker Community Structure, Coral reef community structure on shallow reefs of St. John, US Virgin Islands, 1992-2014. Benthic coral reef communities were monitored on the south shore of St. John. In 1992, six sites were selected using random coordinates constrained to hard bottom on fringing reefs (< 9-m depth) between Cabritte Horn and White Point, and were permanently marked. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/750459, NSF Division of Environmental Biology (NSF DEB) DEB-0841441, NSF Division of Ocean Sciences (NSF OCE) OCE-1332915, NSF Division of Environmental Biology (NSF DEB) DEB-1350146

Published
2021

41. Physical conditions during coral reef surveys of St. John, US Virgin Islands, from 1989-2014

Author

Edmunds, Peter J., Lasker, Howard, Edmunds, Peter J., and Lasker, Howard

Abstract

Dataset: MEPS Edmunds Lasker Physical Data, Physical conditions during coral reef surveys of St. John, US Virgin Islands, from 1989-2014. Benthic coral reef communities were monitored on the south shore of St. John. In 1992, six sites were selected using random coordinates constrained to hard bottom on fringing reefs (< 9-m depth) between Cabritte Horn and White Point, and were permanently marked. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/750558, NSF Division of Environmental Biology (NSF DEB) DEB-0841441, NSF Division of Ocean Sciences (NSF OCE) OCE-1332915, NSF Division of Environmental Biology (NSF DEB) DEB-1350146

Published
2021

44. Embryogenesis, polyembryony, and settlement in the gorgonian Plexaura homomalla

Author

Wells, Christopher D., Tonra, Kaitlyn J., and Lasker, Howard R.

Subjects
Gorgonian, biology, Propagule, Ontogeny, Plexaura homomalla, fungi, Polyembryony, Zoology, Asexual reproduction, Population biology, biology.organism_classification, Full moon
Abstract

Understanding the ontogeny and reproductive biology of reef-building organisms can shed light on patterns of population biology and community structure. This knowledge is particularly important for Caribbean octocorals, which seem to be more resilient to long-term environmental change than scleractinian corals and provide some of the same ecological services. We monitored the development of the black sea rod Plexaura homomalla, a common, widely distributed octocoral on shallow Caribbean reefs, from eggs to 3-polyp colonies over the course of 73 days. In aquaria on St John, U.S. Virgin Islands, gametes were released in spawning events three to six days after the July full moon. Cleavage started 3 hours after fertilization and was holoblastic, equal, and radial. Embryos were positively buoyant until becoming planulae. Planulae were competent after 4 days. Symbiodiniaceae began infecting polyps at around 8 days post fertilization. Development was typical for Caribbean octocorals, except for the occurrence of a novel form of asexual reproduction in octocorals: polyembryony. Fragmentation of embryos during development may represent a temporally varied tradeoff between number and size of propagules, in which large eggs have higher fertilization rates followed by polyembryony, which maximizes the number of surviving recruits by generating more, albeit smaller, larvae. Polyembryony may contribute to the success of some gorgonians on Caribbean reefs as other anthozoans are in decline.

Published
2020

45. Summary sponge abundance by species and site on the coral reefs of St. John USVI from photoquadrats taken between 1992 and 2017

Author

Edmunds, Peter J., Lasker, Howard, Edmunds, Peter J., and Lasker, Howard

Abstract

Dataset: Summary sponge abundance by species and site on the coral reefs of St. John USVI 1992-2017, Abundance of sponges (on both density scale – number per quadrat – and volume scale – estimated volume per quadrat) for three sites over time on the shallow coral reefs of St. John from 1992-2017. Data support Figure S2 in the paper published in Marine Biology (Edumunds et al., 2020). For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/819479, NSF Division of Environmental Biology (NSF DEB) DEB-1350146, NSF Division of Ocean Sciences (NSF OCE) OCE-1756678

Published
2020

46. Octocoral sampling effort (density by pooled taxa and site) from surveys conducted in St. John, US Virgin Islands from 2014 to 2017

Author

Edmunds, Peter J., Lasker, Howard, Edmunds, Peter J., and Lasker, Howard

Abstract

Dataset: Edmunds and Lasker MEPS 2019 Fig S1: Sampling effort, Octocoral sampling effort (density by pooled taxa and site) from surveys conducted in St. John, US Virgin Islands from 2014 to 2017. These data were used in Edmunds and Lasker (2019) Figure S1. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/789188, NSF Division of Ocean Sciences (NSF OCE) OCE-1756678

Published
2020

47. Octocoral colony height by taxon, year, site, and life stage from surveys conducted in St. John, US Virgin Islands from 2014 to 2017

Author

Edmunds, Peter J., Lasker, Howard, Edmunds, Peter J., and Lasker, Howard

Abstract

Dataset: Edmunds and Lasker MEPS 2019 Fig S5b: Height, Octocoral colony height by taxon, year, site, and life stage from surveys conducted in St. John, US Virgin Islands from 2014 to 2017. These data were used in Edmunds and Lasker (2019) Figure S5. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/789217, NSF Division of Ocean Sciences (NSF OCE) OCE-1756678

Published
2020

48. Sponge abundance by species on the coral reefs of St. John USVI from photoquadrats taken between 1992 and 2017

Author

Edmunds, Peter J., Lasker, Howard, Edmunds, Peter J., and Lasker, Howard

Abstract

Dataset: Sponge abundance by species on the coral reefs of St. John USVI 1992-2017, Sponge abundances on the shallow coral reefs of St. John from 1992-2017. Data were extracted from legacy photoquadrats that are part of an ongoing time series, and sponge abundances were expressed as number per quadrat (“Abundance”). Data are presented by taxon, and support Table 1, Figure 4, 5 and S1 in the paper published in Marine Biology (Edumunds et al., 2020). For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/819463, NSF Division of Environmental Biology (NSF DEB) DEB-1350146, NSF Division of Ocean Sciences (NSF OCE) OCE-1756678

Published
2020

49. Summary abundance of soft corals, stony corals, and algae on the reefs of St. John USVI from photoquadrats taken between 1992 and 2017

Author

Edmunds, Peter J., Lasker, Howard, Edmunds, Peter J., and Lasker, Howard

Abstract

Dataset: Summary abundance of soft corals, stony corals, and algae on the reefs of St. John USVI 1992-2017, Abundance of soft corals (number per quadrat [0.25 m2]), stony corals (% cover), macroalgae (% cover), and CTB (a combined group of crustose coralline algae, algal turf, and bare space, % cover) on the shallow coral reefs of St. John from 1992-2017. Data are presented by taxon or functional group, and support Figure 6 in the paper published in Marine Biology (Edumunds et al., 2020). For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/819471, NSF Division of Environmental Biology (NSF DEB) DEB-1350146, NSF Division of Ocean Sciences (NSF OCE) OCE-1756678

Published
2020

50. Octocoral colony heights measured during transect surveys at four sites on the south shore of St. John, US Virgin Islands during June-October 2019

Author

Lasker, Howard, Edmunds, Peter J., Lasker, Howard, and Edmunds, Peter J.

Abstract

Dataset: St John Octocoral Abundances 2019, This dataset contains octocoral colony heights measured during transect surveys at four sites on the south shore of St. John, US Virgin Islands in June-October 2019. These data are a continuation of BCO-DMO project 562086 (http://www.bco-dmo.org/project/562086) and BCO-DMO project 749653 (https://www.bco-dmo.org/project/749653). For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/793259, NSF Division of Ocean Sciences (NSF OCE) OCE-1756381

Published
2020

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