Geographic variation in the vocal behavior of manatees has been reported but is largely unexplore... more Geographic variation in the vocal behavior of manatees has been reported but is largely unexplored. Vocalizations of wild West Indian manatees (Trichechus manatus) were recorded with hydrophones in Florida from Florida manatees (Trichechus manatus latirostris), and in Belize and Panama from Antillean manatees (Trichechus manatus manatus) to determine if calls varied between subspecies and geographic regions. Calls were visually classified into five categories: squeaks, high squeaks, squeals, squeak-squeals, and chirps. From these five categories, only three call types (squeaks, high squeaks and squeals) were observed in all three populations. Six parameters from the temporal and frequency domains were measured from the fundamental frequency of 2878 manatee vocalizations. A repeated measures PERMANOVA found significant differences for squeaks and high squeaks between each geographic location and for squeals between Belize and Florida. Almost all measured frequency and temporal parameters of manatee vocalizations differed between and within subspecies. Variables that may have influenced the variation observed may be related to sex, body size, habitat and/or other factors. Our findings provide critical information of manatee calls for wildlife monitoring and highlight the need for further study of the vocal behavior of manatees throughout their range.
iv 6. The Goff's Caye Management Area is situated due east of Robinson Point. 7. Boundaries of th... more iv 6. The Goff's Caye Management Area is situated due east of Robinson Point. 7. Boundaries of the Gales Point Wildlife Sanctuary as defined by Statutory Instrument 92 of 1996. 8. Turtle nest locations at Gales Point. This important rookery supports hawksbill, green and loggerhead sea turtles. 9. Migration path of the first turtle tracked to Belize, and Robinson Point, in 2000 using satellite telemetry. Zenit, an adult female green turtle, was tagged on her nesting beach in Costa Rica, and about a month later arrived at her foraging ground at Robinson Point. 10. Migration path of Gale shows her travelling into Robinson Point, and then moving south where she resides within the South Water Caye Marine Reserve. 11. Migration path of Caytraveler in 2005 from her nesting beach in Cayman to her foraging ground in Belize. Black dots are bad points that may not be accurate and are not used in the migration path. 12. Migration path of Caytraveler in 2005 as she arrives in Belize and travels to her foraging ground at Robinson Point. Black dots are bad points that may not be accurate and are not used in the migration path.
The red lionfish Pterois volitans is a successful invasive predator across the western North Atla... more The red lionfish Pterois volitans is a successful invasive predator across the western North Atlantic, Caribbean, and Gulf of Mexico. The southeast coast of Florida (USA) has been identified as the original introduction location, but genetic analyses including Florida lionfish have yet to investigate introduction scenarios. Here, we assessed the potential lionfish invasion pathways using 1795 sequences from previously published mitochondrial D-loop sequences (n = 1558) and new samples (n = 237) from 6 locations: The Bahamas, Florida Keys, northwest Florida, North Carolina, Panamá, and southeast Florida. None of the assessed Florida lionfish (n = 394) contained the H05−H09 D-loop haplotypes found in The Bahamas, North Carolina, and Bermuda (the Northern Region), indicating that Florida was not the source for these haplotypes. Assessing the mitochondrial population structure, the Florida east coast lionfish grouped with the Caribbean/ Gulf of Mexico, as opposed to the Northern Region. To further explore connectivity and invasion pathways, 14 nuclear microsatellite loci were multiplexed on lionfish collected from 15 locations (n = 394). As found in other nuclear lionfish studies, the analyses identified a lack of population structure likely due to founding effects and/or inbreeding in aquaculture brood stocks. Together, the significant haplotype differences and H01−H04 haplotypes refute Florida as the sole source of red lionfish introduction. The results of this study support alternative invasion scenarios, in which Florida was colonized as a secondary introduction site or by individuals from the Northern Region. Understanding invasive species' population boundaries and dispersal patterns informs local control efforts and management planning for future invasive species introductions.
Geographic variation in the vocal behavior of manatees has been reported but is largely unexplore... more Geographic variation in the vocal behavior of manatees has been reported but is largely unexplored. Vocalizations of wild West Indian manatees (Trichechus manatus) were recorded with hydrophones in Florida from Florida manatees (Trichechus manatus latirostris), and in Belize and Panama from Antillean manatees (Trichechus manatus manatus) to determine if calls varied between subspecies and geographic regions. Calls were visually classified into five categories: squeaks, high squeaks, squeals, squeak-squeals, and chirps. From these five categories, only three call types (squeaks, high squeaks and squeals) were observed in all three populations. Six parameters from the temporal and frequency domains were measured from the fundamental frequency of 2878 manatee vocalizations. A repeated measures PERMANOVA found significant differences for squeaks and high squeaks between each geographic location and for squeals between Belize and Florida. Almost all measured frequency and temporal parame...
Red lionfish (Pterois volitans) have become a successful invasive predator across the Northwester... more Red lionfish (Pterois volitans) have become a successful invasive predator across the Northwestern Atlantic, Caribbean, and Gulf of Mexico (GoM). Previous investigations have identified the southeast coast of Florida as the original site of introduction, but no region-wide genetic study has directly addressed the question of introduction location(s). This dataset includes previously unpublished red lionfish samples (n = 237) from six locations: The Bahamas, Florida Keys, Northwest Florida, North Carolina, Panama, and Southeast Florida. Sequences archived in NCBI from other locations in the Northern Region, Caribbean, and Gulf of Mexico basins were used in the analyses (N = 1558). Previously published sequences were obtained from Freshwater et al. (2009) (N = 396), Sealy et al. (2013) (N = 178), Whitaker and Janosik (2020) (N = 80), Butterfield et al. (2015) (N = 214), Toledo-Hernandez et al. (2014) (N = 118), Betancur-R et al. (2011) (N = 337), and Johnson et al. (2016) (N = 235). P...
Anecdotal reports, flipper tag returns, satellite migration paths, and above-water and net survey... more Anecdotal reports, flipper tag returns, satellite migration paths, and above-water and net surveys have identified an important foraging area for sea turtles in the Robinson Point area, 12 kilometers southwest of Belize City. Visual observations confirmed that sea turtles were actively foraging at Robinson Point. Sixteen 30 minute visual observations from stationary and drifting boats made 132 sea turtle sightings from October 2007 through January 2008, with a maximum of 40 sightings made in one survey. In-water capture methodology tested the traditional turtle net, which captured 14 turtles in 63 sets for a success rate of only 22%. There were 11 green turtles captured during the migratory months from April through October, and three hawksbill turtles were captured during non-migratory months, November through March, indicating that both species were resident at Robinson Point. No loggerheads, adult males, or juvenile turtles were captured, but anecdotal reports confirmed presence....
The red lionfish Pterois volitans is a successful invasive predator across the western North Atla... more The red lionfish Pterois volitans is a successful invasive predator across the western North Atlantic, Caribbean, and Gulf of Mexico. The southeast coast of Florida (USA) has been identified as the original introduction location, but genetic analyses including Florida lionfish have yet to investigate introduction scenarios. Here, we assessed the potential lionfish invasion pathways using 1795 sequences from previously published mitochondrial D-loop sequences (n = 1558) and new samples (n = 237) from 6 locations: The Bahamas, Florida Keys, northwest Florida, North Carolina, Panamá, and southeast Florida. None of the assessed Florida lionfish (n = 394) contained the H05-H09 D-loop haplotypes found in The Bahamas, North Carolina, and Bermuda (the Northern Region), indicating that Florida was not the source for these haplotypes. Assessing the mitochondrial population structure, the Florida east coast lionfish grouped with the Caribbean/Gulf of Mexico, as opposed to the Northern Region. ...
Population assessments and species monitoring for many endangered marine megafauna are limited by... more Population assessments and species monitoring for many endangered marine megafauna are limited by the challenges of identifying and tracking individuals that live underwater in remote and sometimes inaccessible areas. Manatees can acquire scars from watercraft injury and other incidences that can be used to identify individuals. Here we describe a novel method for photo-identification of Antillean manatees Trichechus manatus manatus using aerial imagery captured during flights with a small multirotor drone. Between 2016 and 2017, we conducted 103 flights to detect and observe manatees in Belize, primarily at St. George's Caye (SGC) near the Belize Barrier Reef. Review of aerial videos from these flights resulted in 279 sightings of manatees (245 adults, 34 calves). High-resolution images of individual manatees were extracted and classified according to image quality and distinctiveness of individual manatees for photoidentification. High-quality images of manatees classified as sufficiently distinctive were used to create a catalog of 17 identifiable individuals. At SGC, 21% of all sighted adult manatees (N = 214) were considered photo-identifiable over time. We suggest that the method can be used for investigating individual site fidelity, habitat use, and behavior of manatee populations. Our photoidentification protocol has the potential to improve long-term monitoring of Antillean manatees in Belize and can be applied throughout clear, shallow waters in the Caribbean and elsewhere.
h = 0.59). Using haplotype population pairwise Φ ST tests, we analyzed possible phylogeographic b... more h = 0.59). Using haplotype population pairwise Φ ST tests, we analyzed possible phylogeographic breaks that were previously proposed based on other reef organisms. We found support for the Bahamas/Turks/Caicos versus Caribbean break (Φ ST = 0.12) but not for the Northwestern Caribbean, Eastern Caribbean, or US East Coast versus Bahamas breaks. The Northern Region had higher variation and more haplotypes, supporting introductions of at least five haplotypes to the region. Our wide-ranging samples showed that a lower-frequency haplotype in the Northern Region dominated the Southern Region and suggested multiple introductions, possibly to the south. We tested multiple scenarios of phylogeographic structure with analyses of molecular variance and found support for a Northern and Southern Region split at the Bahamas/Turks/Caicos versus Caribbean break (percentage of variation among regions = 8.49 %). We found that Puerto Rico clustered with the Southern Region more strongly than with the Northern Region, as opposed to previous reports. We also found the rare haplotype H03 for the first time in the southern Caribbean (Panama), indicating that either secondary releases occurred or that the lowfrequency haplotypes have had time to disperse to extreme southern Caribbean locations.
Geographic variation in the vocal behavior of manatees has been reported but is largely unexplore... more Geographic variation in the vocal behavior of manatees has been reported but is largely unexplored. Vocalizations of wild West Indian manatees (Trichechus manatus) were recorded with hydrophones in Florida from Florida manatees (Trichechus manatus latirostris), and in Belize and Panama from Antillean manatees (Trichechus manatus manatus) to determine if calls varied between subspecies and geographic regions. Calls were visually classified into five categories: squeaks, high squeaks, squeals, squeak-squeals, and chirps. From these five categories, only three call types (squeaks, high squeaks and squeals) were observed in all three populations. Six parameters from the temporal and frequency domains were measured from the fundamental frequency of 2878 manatee vocalizations. A repeated measures PERMANOVA found significant differences for squeaks and high squeaks between each geographic location and for squeals between Belize and Florida. Almost all measured frequency and temporal parameters of manatee vocalizations differed between and within subspecies. Variables that may have influenced the variation observed may be related to sex, body size, habitat and/or other factors. Our findings provide critical information of manatee calls for wildlife monitoring and highlight the need for further study of the vocal behavior of manatees throughout their range.
iv 6. The Goff's Caye Management Area is situated due east of Robinson Point. 7. Boundaries of th... more iv 6. The Goff's Caye Management Area is situated due east of Robinson Point. 7. Boundaries of the Gales Point Wildlife Sanctuary as defined by Statutory Instrument 92 of 1996. 8. Turtle nest locations at Gales Point. This important rookery supports hawksbill, green and loggerhead sea turtles. 9. Migration path of the first turtle tracked to Belize, and Robinson Point, in 2000 using satellite telemetry. Zenit, an adult female green turtle, was tagged on her nesting beach in Costa Rica, and about a month later arrived at her foraging ground at Robinson Point. 10. Migration path of Gale shows her travelling into Robinson Point, and then moving south where she resides within the South Water Caye Marine Reserve. 11. Migration path of Caytraveler in 2005 from her nesting beach in Cayman to her foraging ground in Belize. Black dots are bad points that may not be accurate and are not used in the migration path. 12. Migration path of Caytraveler in 2005 as she arrives in Belize and travels to her foraging ground at Robinson Point. Black dots are bad points that may not be accurate and are not used in the migration path.
The red lionfish Pterois volitans is a successful invasive predator across the western North Atla... more The red lionfish Pterois volitans is a successful invasive predator across the western North Atlantic, Caribbean, and Gulf of Mexico. The southeast coast of Florida (USA) has been identified as the original introduction location, but genetic analyses including Florida lionfish have yet to investigate introduction scenarios. Here, we assessed the potential lionfish invasion pathways using 1795 sequences from previously published mitochondrial D-loop sequences (n = 1558) and new samples (n = 237) from 6 locations: The Bahamas, Florida Keys, northwest Florida, North Carolina, Panamá, and southeast Florida. None of the assessed Florida lionfish (n = 394) contained the H05−H09 D-loop haplotypes found in The Bahamas, North Carolina, and Bermuda (the Northern Region), indicating that Florida was not the source for these haplotypes. Assessing the mitochondrial population structure, the Florida east coast lionfish grouped with the Caribbean/ Gulf of Mexico, as opposed to the Northern Region. To further explore connectivity and invasion pathways, 14 nuclear microsatellite loci were multiplexed on lionfish collected from 15 locations (n = 394). As found in other nuclear lionfish studies, the analyses identified a lack of population structure likely due to founding effects and/or inbreeding in aquaculture brood stocks. Together, the significant haplotype differences and H01−H04 haplotypes refute Florida as the sole source of red lionfish introduction. The results of this study support alternative invasion scenarios, in which Florida was colonized as a secondary introduction site or by individuals from the Northern Region. Understanding invasive species' population boundaries and dispersal patterns informs local control efforts and management planning for future invasive species introductions.
Geographic variation in the vocal behavior of manatees has been reported but is largely unexplore... more Geographic variation in the vocal behavior of manatees has been reported but is largely unexplored. Vocalizations of wild West Indian manatees (Trichechus manatus) were recorded with hydrophones in Florida from Florida manatees (Trichechus manatus latirostris), and in Belize and Panama from Antillean manatees (Trichechus manatus manatus) to determine if calls varied between subspecies and geographic regions. Calls were visually classified into five categories: squeaks, high squeaks, squeals, squeak-squeals, and chirps. From these five categories, only three call types (squeaks, high squeaks and squeals) were observed in all three populations. Six parameters from the temporal and frequency domains were measured from the fundamental frequency of 2878 manatee vocalizations. A repeated measures PERMANOVA found significant differences for squeaks and high squeaks between each geographic location and for squeals between Belize and Florida. Almost all measured frequency and temporal parame...
Red lionfish (Pterois volitans) have become a successful invasive predator across the Northwester... more Red lionfish (Pterois volitans) have become a successful invasive predator across the Northwestern Atlantic, Caribbean, and Gulf of Mexico (GoM). Previous investigations have identified the southeast coast of Florida as the original site of introduction, but no region-wide genetic study has directly addressed the question of introduction location(s). This dataset includes previously unpublished red lionfish samples (n = 237) from six locations: The Bahamas, Florida Keys, Northwest Florida, North Carolina, Panama, and Southeast Florida. Sequences archived in NCBI from other locations in the Northern Region, Caribbean, and Gulf of Mexico basins were used in the analyses (N = 1558). Previously published sequences were obtained from Freshwater et al. (2009) (N = 396), Sealy et al. (2013) (N = 178), Whitaker and Janosik (2020) (N = 80), Butterfield et al. (2015) (N = 214), Toledo-Hernandez et al. (2014) (N = 118), Betancur-R et al. (2011) (N = 337), and Johnson et al. (2016) (N = 235). P...
Anecdotal reports, flipper tag returns, satellite migration paths, and above-water and net survey... more Anecdotal reports, flipper tag returns, satellite migration paths, and above-water and net surveys have identified an important foraging area for sea turtles in the Robinson Point area, 12 kilometers southwest of Belize City. Visual observations confirmed that sea turtles were actively foraging at Robinson Point. Sixteen 30 minute visual observations from stationary and drifting boats made 132 sea turtle sightings from October 2007 through January 2008, with a maximum of 40 sightings made in one survey. In-water capture methodology tested the traditional turtle net, which captured 14 turtles in 63 sets for a success rate of only 22%. There were 11 green turtles captured during the migratory months from April through October, and three hawksbill turtles were captured during non-migratory months, November through March, indicating that both species were resident at Robinson Point. No loggerheads, adult males, or juvenile turtles were captured, but anecdotal reports confirmed presence....
The red lionfish Pterois volitans is a successful invasive predator across the western North Atla... more The red lionfish Pterois volitans is a successful invasive predator across the western North Atlantic, Caribbean, and Gulf of Mexico. The southeast coast of Florida (USA) has been identified as the original introduction location, but genetic analyses including Florida lionfish have yet to investigate introduction scenarios. Here, we assessed the potential lionfish invasion pathways using 1795 sequences from previously published mitochondrial D-loop sequences (n = 1558) and new samples (n = 237) from 6 locations: The Bahamas, Florida Keys, northwest Florida, North Carolina, Panamá, and southeast Florida. None of the assessed Florida lionfish (n = 394) contained the H05-H09 D-loop haplotypes found in The Bahamas, North Carolina, and Bermuda (the Northern Region), indicating that Florida was not the source for these haplotypes. Assessing the mitochondrial population structure, the Florida east coast lionfish grouped with the Caribbean/Gulf of Mexico, as opposed to the Northern Region. ...
Population assessments and species monitoring for many endangered marine megafauna are limited by... more Population assessments and species monitoring for many endangered marine megafauna are limited by the challenges of identifying and tracking individuals that live underwater in remote and sometimes inaccessible areas. Manatees can acquire scars from watercraft injury and other incidences that can be used to identify individuals. Here we describe a novel method for photo-identification of Antillean manatees Trichechus manatus manatus using aerial imagery captured during flights with a small multirotor drone. Between 2016 and 2017, we conducted 103 flights to detect and observe manatees in Belize, primarily at St. George's Caye (SGC) near the Belize Barrier Reef. Review of aerial videos from these flights resulted in 279 sightings of manatees (245 adults, 34 calves). High-resolution images of individual manatees were extracted and classified according to image quality and distinctiveness of individual manatees for photoidentification. High-quality images of manatees classified as sufficiently distinctive were used to create a catalog of 17 identifiable individuals. At SGC, 21% of all sighted adult manatees (N = 214) were considered photo-identifiable over time. We suggest that the method can be used for investigating individual site fidelity, habitat use, and behavior of manatee populations. Our photoidentification protocol has the potential to improve long-term monitoring of Antillean manatees in Belize and can be applied throughout clear, shallow waters in the Caribbean and elsewhere.
h = 0.59). Using haplotype population pairwise Φ ST tests, we analyzed possible phylogeographic b... more h = 0.59). Using haplotype population pairwise Φ ST tests, we analyzed possible phylogeographic breaks that were previously proposed based on other reef organisms. We found support for the Bahamas/Turks/Caicos versus Caribbean break (Φ ST = 0.12) but not for the Northwestern Caribbean, Eastern Caribbean, or US East Coast versus Bahamas breaks. The Northern Region had higher variation and more haplotypes, supporting introductions of at least five haplotypes to the region. Our wide-ranging samples showed that a lower-frequency haplotype in the Northern Region dominated the Southern Region and suggested multiple introductions, possibly to the south. We tested multiple scenarios of phylogeographic structure with analyses of molecular variance and found support for a Northern and Southern Region split at the Bahamas/Turks/Caicos versus Caribbean break (percentage of variation among regions = 8.49 %). We found that Puerto Rico clustered with the Southern Region more strongly than with the Northern Region, as opposed to previous reports. We also found the rare haplotype H03 for the first time in the southern Caribbean (Panama), indicating that either secondary releases occurred or that the lowfrequency haplotypes have had time to disperse to extreme southern Caribbean locations.
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