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Satellite tracking of sympatric marine megafauna can inform the biological basis for species co-management.

Gredzens C, Marsh H, Fuentes MM, Limpus CJ, Shimada T, Hamann M - PLoS ONE (2014)

Bottom Line: Additionally, sympatric and inter-related species are often managed separately, which may not be cost-effective.Home-range analysis and bathymetric modeling were used to determine spatial use and compared with existing protection areas using GIS.Dugong and green turtle home-ranges significantly overlapped in both locations.

View Article: PubMed Central - PubMed

Affiliation: School of Earth and Environmental Sciences, James Cook University, Townsville, Queensland, Australia; School of Marine and Tropical Biology, James Cook University, Townsville, Queensland, Australia.

ABSTRACT

Context: Systematic conservation planning is increasingly used to identify priority areas for protection in marine systems. However, ecosystem-based approaches typically use density estimates as surrogates for animal presence and spatial modeling to identify areas for protection and may not take into account daily or seasonal movements of animals. Additionally, sympatric and inter-related species are often managed separately, which may not be cost-effective. This study aims to demonstrate an evidence-based method to inform the biological basis for co-management of two sympatric species, dugongs and green sea turtles. This approach can then be used in conservation planning to delineate areas to maximize species protection.

Methodology/results: Fast-acquisition satellite telemetry was used to track eleven dugongs and ten green turtles at two geographically distinct foraging locations in Queensland, Australia to evaluate the inter- and intra-species spatial relationships and assess the efficacy of existing protection zones. Home-range analysis and bathymetric modeling were used to determine spatial use and compared with existing protection areas using GIS. Dugong and green turtle home-ranges significantly overlapped in both locations. However, both species used different core areas and differences existed between regions in depth zone use and home-range size, especially for dugongs. Both species used existing protection areas in Shoalwater Bay, but only a single tracked dugong used the existing protection area in Torres Strait.

Conclusions/significance: Fast-acquisition satellite telemetry can provide evidence-based information on individual animal movements to delineate relationships between dugongs and green turtles in regions where they co-occur. This information can be used to increase the efficacy of conservation planning and complement more broadly based survey information. These species also use similar habitats, making complimentary co-management possible, but important differences exist between locations making it essential to customize management. This methodology could be applied on a broader scale to include other sympatric and inter-related species.

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Related in: MedlinePlus

Shoalwater Bay dugong and green turtle spatial use.Dugong and green sea turtle tracking and foraging home-ranges within Shoalwater Bay, Australia using the total tracking duration of each animal. Blue features indicate dugongs and red features indicate green sea turtles. (A) Tracking locations and migratory path of the transient dugong (652636A). (B and C) Example home-ranges of dugongs (B: 652642A, C: 652640A (left) and 652643A (right)). (D and E) Example home-ranges of green sea turtles (D: 96780 (left), 108469 (middle), and 120640 (right); E: 120641). (F) Comparison of dugong and green sea turtle 50% core areas in northwestern Shoalwater Bay. Gray box indicates region displayed in maps B-F. For maps with multiple individuals plotted, each individual's 95% home-range is delineated by hatching at a different angle. Note differences in scale for each map.
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pone-0098944-g002: Shoalwater Bay dugong and green turtle spatial use.Dugong and green sea turtle tracking and foraging home-ranges within Shoalwater Bay, Australia using the total tracking duration of each animal. Blue features indicate dugongs and red features indicate green sea turtles. (A) Tracking locations and migratory path of the transient dugong (652636A). (B and C) Example home-ranges of dugongs (B: 652642A, C: 652640A (left) and 652643A (right)). (D and E) Example home-ranges of green sea turtles (D: 96780 (left), 108469 (middle), and 120640 (right); E: 120641). (F) Comparison of dugong and green sea turtle 50% core areas in northwestern Shoalwater Bay. Gray box indicates region displayed in maps B-F. For maps with multiple individuals plotted, each individual's 95% home-range is delineated by hatching at a different angle. Note differences in scale for each map.

Mentions: All five dugongs were individualistic in their movements. The four dugongs with small 95% home-ranges (<75 km2) were resident within the northwest portion of Shoalwater Bay between Clara Island and MacDonald Point for most of the tracking period (Figure 2B,C). One of these dugongs (652631A – male, 141 days) relocated approximately 90 km to the west near Clairview on 26 September 2012 (after two days at large) and spent the remainder of its tracking time at this location.


Satellite tracking of sympatric marine megafauna can inform the biological basis for species co-management.

Gredzens C, Marsh H, Fuentes MM, Limpus CJ, Shimada T, Hamann M - PLoS ONE (2014)

Shoalwater Bay dugong and green turtle spatial use.Dugong and green sea turtle tracking and foraging home-ranges within Shoalwater Bay, Australia using the total tracking duration of each animal. Blue features indicate dugongs and red features indicate green sea turtles. (A) Tracking locations and migratory path of the transient dugong (652636A). (B and C) Example home-ranges of dugongs (B: 652642A, C: 652640A (left) and 652643A (right)). (D and E) Example home-ranges of green sea turtles (D: 96780 (left), 108469 (middle), and 120640 (right); E: 120641). (F) Comparison of dugong and green sea turtle 50% core areas in northwestern Shoalwater Bay. Gray box indicates region displayed in maps B-F. For maps with multiple individuals plotted, each individual's 95% home-range is delineated by hatching at a different angle. Note differences in scale for each map.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4043907&req=5

pone-0098944-g002: Shoalwater Bay dugong and green turtle spatial use.Dugong and green sea turtle tracking and foraging home-ranges within Shoalwater Bay, Australia using the total tracking duration of each animal. Blue features indicate dugongs and red features indicate green sea turtles. (A) Tracking locations and migratory path of the transient dugong (652636A). (B and C) Example home-ranges of dugongs (B: 652642A, C: 652640A (left) and 652643A (right)). (D and E) Example home-ranges of green sea turtles (D: 96780 (left), 108469 (middle), and 120640 (right); E: 120641). (F) Comparison of dugong and green sea turtle 50% core areas in northwestern Shoalwater Bay. Gray box indicates region displayed in maps B-F. For maps with multiple individuals plotted, each individual's 95% home-range is delineated by hatching at a different angle. Note differences in scale for each map.
Mentions: All five dugongs were individualistic in their movements. The four dugongs with small 95% home-ranges (<75 km2) were resident within the northwest portion of Shoalwater Bay between Clara Island and MacDonald Point for most of the tracking period (Figure 2B,C). One of these dugongs (652631A – male, 141 days) relocated approximately 90 km to the west near Clairview on 26 September 2012 (after two days at large) and spent the remainder of its tracking time at this location.

Bottom Line: Additionally, sympatric and inter-related species are often managed separately, which may not be cost-effective.Home-range analysis and bathymetric modeling were used to determine spatial use and compared with existing protection areas using GIS.Dugong and green turtle home-ranges significantly overlapped in both locations.

View Article: PubMed Central - PubMed

Affiliation: School of Earth and Environmental Sciences, James Cook University, Townsville, Queensland, Australia; School of Marine and Tropical Biology, James Cook University, Townsville, Queensland, Australia.

ABSTRACT

Context: Systematic conservation planning is increasingly used to identify priority areas for protection in marine systems. However, ecosystem-based approaches typically use density estimates as surrogates for animal presence and spatial modeling to identify areas for protection and may not take into account daily or seasonal movements of animals. Additionally, sympatric and inter-related species are often managed separately, which may not be cost-effective. This study aims to demonstrate an evidence-based method to inform the biological basis for co-management of two sympatric species, dugongs and green sea turtles. This approach can then be used in conservation planning to delineate areas to maximize species protection.

Methodology/results: Fast-acquisition satellite telemetry was used to track eleven dugongs and ten green turtles at two geographically distinct foraging locations in Queensland, Australia to evaluate the inter- and intra-species spatial relationships and assess the efficacy of existing protection zones. Home-range analysis and bathymetric modeling were used to determine spatial use and compared with existing protection areas using GIS. Dugong and green turtle home-ranges significantly overlapped in both locations. However, both species used different core areas and differences existed between regions in depth zone use and home-range size, especially for dugongs. Both species used existing protection areas in Shoalwater Bay, but only a single tracked dugong used the existing protection area in Torres Strait.

Conclusions/significance: Fast-acquisition satellite telemetry can provide evidence-based information on individual animal movements to delineate relationships between dugongs and green turtles in regions where they co-occur. This information can be used to increase the efficacy of conservation planning and complement more broadly based survey information. These species also use similar habitats, making complimentary co-management possible, but important differences exist between locations making it essential to customize management. This methodology could be applied on a broader scale to include other sympatric and inter-related species.

Show MeSH
Related in: MedlinePlus