Antonio A. Mignucci-Giannoni

Phylogeography of the West Indian manatee (Trichechus manatus): how many populations and how many taxa?

To resolve the population genetic structure and phylogeography of the West Indian manatee (Trichechus manatus), mitochondrial (mt) DNA control region sequences were compared among eight locations across the western Atlantic region. Fifteen haplotypes were identified among 86 individuals from Florida, Puerto Rico, the Dominican Republic, Mexico, Colombia, Venezuela, Guyana and Brazil. Despite the manatee’s ability to move thousands of kilometres along continental margins, strong population separations between most locations were demonstrated with significant haplotype frequency shifts. These findings are consistent with tagging studies which indicate that stretches of open water and unsuitable coastal habitats constitute substantial barriers to gene flow and colonization. Low levels of genetic diversity within Florida and Brazilian samples might be explained by recent colonization into high latitudes or bottleneck effects. Three distinctive mtDNA lineages were observed in an intraspecific phylogeny of T. manatus, corresponding approximately to: (i) Florida and the West Indies; (ii) the Gulf of Mexico to the Caribbean rivers of South America; and (iii) the northeast Atlantic coast of South America. These lineages, which are not concordant with previous subspecies designations, are separated by sequence divergence estimates of d = 0.04–0.07, approximately the same level of divergence observed between T. manatus and the Amazonian manatee (T. inunguis, n = 16). Three individuals from Guyana, identified as T. manatus, had mtDNA haplotypes which are affiliated with the endemic Amazon form T. inunguis. The three primary T. manatus lineages and the T. inunguis lineage may represent relatively deep phylogeographic partitions which have been bridged recently due to changes in habitat availability (after the Wisconsin glacial period, 10 000 BP), natural colonization, and human‐mediated transplantation.

Female philopatry in coastal basins and male dispersion across the North Atlantic in a highly mobile marine species, the sperm whale (Physeter macrocephalus).

The mechanisms that determine population structure in highly mobile marine species are poorly understood, but useful towards understanding the evolution of diversity, and essential for effective conservation and management. In this study, we compare putative sperm whale populations located in the Gulf of Mexico, western North Atlantic, Mediterranean Sea and North Sea using mtDNA control region sequence data and 16 polymorphic microsatellite loci. The Gulf of Mexico, western North Atlantic and North Sea populations each possessed similar low levels of haplotype and nucleotide diversity at the mtDNA locus, while the Mediterranean Sea population showed no detectable mtDNA diversity. Mitochondrial DNA results showed significant differentiation between all populations, while microsatellites showed significant differentiation only for comparisons with the Mediterranean Sea, and at a much lower level than seen for mtDNA. Samples from either side of the North Atlantic in coastal waters showed no differentiation for mtDNA, while North Atlantic samples from just outside the Gulf of Mexico (the western North Atlantic sample) were highly differentiated from samples within the Gulf at this locus. Our analyses indicate a previously unknown fidelity of females to coastal basins either side of the North Atlantic, and suggest the movement of males among these populations for breeding.

Phylogeography, phylogeny and hybridization in trichechid sirenians: implications for manatee conservation

The three living species of manatees, West Indian (Trichechus manatus), Amazonian (Trichechus inunguis) and West African (Trichechus senegalensis), are distributed across the shallow tropical and subtropical waters of America and the western coast of Africa. We have sequenced the mitochondrial DNA control region in 330 Trichechus to compare their phylogeographic patterns. In T. manatus we observed a marked population structure with the identification of three haplotype clusters showing a distinct spatial distribution. A geographic barrier represented by the continuity of the Lesser Antilles to Trinidad Island, near the mouth of the Orinoco River in Venezuela, appears to have restricted the gene flow historically in T. manatus. However, for T. inunguis we observed a single expanding population cluster, with a high diversity of very closely related haplotypes. A marked geographic population structure is likely present in T. senegalensis with at least two distinct clusters. Phylogenetic analyses with the mtDNA cytochrome b gene suggest a clade of the marine Trichechus species, with T. inunguis as the most basal trichechid. This is in agreement with previous morphological analyses. Mitochondrial DNA, autosomal microsatellites and cytogenetic analyses revealed the presence of hybrids between the T. manatus and T. inunguis species at the mouth of the Amazon River in Brazil, extending to the Guyanas and probably as far as the mouth of the Orinoco River. Future conservation strategies should consider the distinct population structure of manatee species, as well as the historical barriers to gene flow and the likely occurrence of interspecific hybridization.

Worldwide structure of mtDNA diversity among Cuvier's beaked whales (Ziphius cavirostris): implications for threatened populations

We present the first description of phylogeographic structure among Cuviers beaked whales (Ziphius cavirostris) worldwide using mitochondrial DNA (mtDNA) control region sequences obtained from strandings (n = 70), incidental fisheries takes (n = 11), biopsy (n = 1), and whale‐meat markets (n = 5). Over a 290‐base pair fragment, 23 variable sites defined 33 unique haplotypes among the total of 87 samples. Nucleotide diversity at the control region was relatively low (π = 1.27%± 0.723%) compared to wide‐ranging baleen whales, but higher than strongly matrifocal sperm, pilot and killer whales. Phylogenetic reconstruction using maximum likelihood revealed four distinct haplotype groups, each of which displayed strong frequency differences among ocean basins, but no reciprocal monophyly or fixed character differences. Consistent with this phylogeographic pattern, an analysis of molecular variance showed high levels of differentiation among ocean basins (FST = 0.14, ΦST = 0.42; P < 0.001). Estimated rates of female migration among ocean basins were low (generally ≤ 2 individuals per generation). Regional sample sizes were too small to detect subdivisions within oceans except in the North Atlantic, where the Mediterranean Sea (n = 12) was highly differentiated due to the presence of two private haplotypes. One market product purchased in South Korea grouped with other haplotypes found only in the North Atlantic, suggesting a violation of current agreements banning international trade in cetacean species. Together, these results demonstrate a high degree of isolation and low maternal gene flow among oceanic, and in some cases, regional populations of Cuviers beaked whales. This has important implications for understanding the threats of human impact, including fisheries by‐catch, direct hunting, and disturbance or mortality from anthropogenic sound.

An Epizootic of Cutaneous Fibropapillomas in Green Turtles Chelonia mydas of the Caribbean: Part of a Panzootic?

Abstract An epizootic of fibropapillomas in green turtles Chelonia mydas (Reptilia: Testudines: Cheloniidae) has occurred throughout the Caribbean since the mid-1980s. Similar epizootics in Hawaii and Florida began 5 years earlier. All may be part of a panzootic. The 125 Caribbean cases greatly expand the known range of these epizootics. All the tumors we examined had spirorchiid (Digenea) eggs. Few turtles we examined with tumors were emaciated. Additional tumors quickly erupted in some captive turtles, whereas tumors of others remained unchanged for 1 year. The turtle leech Ozobranchus branchiatus (Hirudinea: Ozobranchidae) was associated with only three green turtles with fibropapillomas.

Metazoan Parasites and Other Symbionts of Cetaceans in the Caribbean

The parasite fauna in cetaceans from Puerto Rico, the Virgin Islands, and the larger Caribbean region is poorly known. We provide the first records for parasite biodiversity among a diverse assemblage of cetaceans from the Caribbean Sea. Internal and external parasites and commensals were collected from stranded whales and dolphins salvaged in Puerto Rico, the United States and British Virgin Islands, Jamaica, and Venezuela between 1989 and 1997. A total of 47 individuals of 16 species of whales and dolphins (15 odontocetes and 1 mysticete) was examined. Overall, parasites and commensals were found in 34 (72.3%) animals, representing 13 species of odontocetes and 1 mysticete. Eighteen species of endoparasitic helminths were found, including 8 species of nematodes, 2 digeneans, 6 cestodes, and 2 acanthocephalans. Three species of whale-lice and 2 species of barnacles were also collected.

Mass stranding of pygmy killer whales ( Feresa attenuata ) in the British Virgin Islands

The pygmy killer whale ( Feresa attenuata ) is an offshore, tropical and subtropical delphinid found in the Atlantic, Indian and Pacific Oceans. The species has only recently been studied, mostly from specimens collected from strandings. While over 52 reports exist for the Atlantic Ocean, only one record exists for the Caribbean Sea. A new record of a mass stranding of pygmy killer whales from the British Virgin Islands is documented and the pathology and life history of the specimens is described, associating the stranding process with the meteorological and oceanographic disturbance of Hurricane Marilyn, which devastated the Virgin Islands a day prior to the stranding. This stranding event constitutes the sixth known mass stranding for the species worldwide, the first record for pygmy killer whales for the northeastern Caribbean and the second for the entire Caribbean Sea.

Helminth and arthropod parasites of the brown pelican, Pelecanus occidentalis , in Puerto Rico, with a compilation of all metazoan parasites reported from this host in the Western Hemisphere

Seven species of helminths and six species of arthropods are reported from 23 of 40 brown pelicans, Pelecanus occidentalis , collected from various localities in Puerto Rico. Helminth parasites include three nematodes ( Contracaecum multipapillatum , Contracaecum mexicanum , and Eustrongylides sp.), three trematodes ( Galactosomum darbyi , Mesostephanus appendiculatoides , and Ribeiroia ondatrae ), and one cestode ( Tetrabothrium sulae ). Arthropod parasites include Colpocephalum occidentalis , Neottialges apunctatus , Ornithodoros capensis, Phalacrodectus pelecani, Phalacrodectus punctatissimus , and Phalacrodectus sp. The presence of R. ondatrae in the brown pelican is a new species host record, and P. pelecani, P. punctatissimus and N. apunctatus are new subspecies host records. C. multipapillatum , C. mexicanum , G. darbyi and M. appendiculatoides are new locality records for Puerto Rico, and N. apunctatus, P. pelecani, P. punctatissimus and T. sulae are new locality records for the Caribbean. Necrosis produced by C. multipapillatum , C. mexicanum , and R. ondatrae may have contributed to the emaciation and death of the brown pelicans examined in the present study.

Assessment and rehabilitation of wildlife affected by an oil spill in Puerto Rico

On 7 January 1994, the barge Morris J. Berman spilled approximately 3.6 million liters of oil off Punta Escambron in San Juan, Puerto Rico. This resulted in the contamination of extensive areas, impacting on natural resources along more than 48 km of Puerto Ricos north shore. Thousands of dead and live oiled organisms washed ashore. Dead wildlife were collected opportunistically, and examined for the presence of oil and identified. Live wildlife was cleaned and treated at a temporary triage facility. A total of 5687 organisms of over 152 species were collected, including cnidarians, annelids, crustaceans, molluscs, echinoderms, fishes, birds and sea turtles. Molluscs and echinoderms were noticeably more affected than other species. Four species classified as endangered or threatened were also affected. A significant impact was observed on the live specimens presented for medical treatment, including shore crabs, birds and sea turtles. Only 63% of these were successfully rehabilitated.

New Leeches and Diseases for the Hawksbill Sea Turtle and the West Indies

Abstract The Green sea turtle leech, Ozobranchus brachiatus, infected a moribund hawksbill sea turtle (Eretomochelys imbricata) posthatchling juvenile at Farjardo, Puerto Rico. It usually infects green sea turtles, Chelonia mydas, and has not been reported from wild E. imbriata. A superinfection of the loggerhead sea turtle leech, Ozobranchus margoi, occurred on a stranded E. imbricata at Vieques Island, causing sea turtle leech erosion disease (SLED). We name and describe this disease for the first time. Ozobranchus margoi usually infects loggerhead sea turtles, Caretta caretta, and has not previously been reported either from the West Indies or confirmed from wild hawksbill sea turtles. In Barbados, O. margoi was first associated with a nesting female E. imbricata in 1997, and has been seen in other individuals since. SLED has not previously been reported from wild sea turtles or from the West Indies.