Mesophotic coral ecosystems under anthropogenic stress: a case study at Ponce,Puerto Rico

Mesophotic coral ecosystems (MCEs) were compared between La Parguera and Ponce, off the south coast of Puerto Rico. In contrast to La Parguera, Ponce has a narrow insular shelf and hosts several river outlets, a commercial port, a regional sewage treatment plant with associated deep water outfall, and three deep dredge disposal sites. Off Ponce, MCEs receive higher (16×) rates of sedimentation than off La Parguera, a less impacted site. The most impacted sites were located offshore of Cayo Ratones and are in or down-current and in close proximity to one of the dredge disposal sites. There, MCEs are characterized by a steep, irregular, rocky slope with a cover of fine-grained, dark brown sediment, which increases with depth. At shallower depths, scattered rocky outcroppings are colonized by sponges, black corals and algae. The sediment cover contains two to three times the terrigenous content and a significantly higher percentage of the fine-grained fraction than off La Parguera. Thirteen remotely operated vehicle (ROV) dives east and west of Ponce showed that the deepest depth at which corals were observed increased with distance from Cayo Ratones and did not approach depths observed off La Parguera except at the eastern-most (up-current) site, Caja de Muertos, which was also significantly further offshore. Benthic communities off Caja de Muertos were comparable to those at La Parguera, while off Cayo Ratones, there were no mesophotic corals and sparse development of other benthic macrobiota except sponges. Management authorities should include MCEs when assessing potential impacts from anthropogenic activities and take the necessary steps to reduce local threats.     

Negotiation of ethnoracial configurations among Puerto Rican Taíno activists

In Puerto Rico, scholarly histories and common knowledge have presumed that the Taíno – the pre-Columbian population of the island – became extinct at some time between the sixteenth and eighteenth centuries. However, various people on the island challenge this assumption by claiming to be Taíno. The public reemergence of Taíno groups in Puerto Rico is highly disputed by scholars, governmental institutions and non-Taíno populations of the region, often on the basis of Puerto Rico’s long-documented history of creolization and state-sponsored ideology of racial blending. Within this context, the case of Taíno indigenous activism in Puerto Rico offers a critical lens through which to consider interactional challenges involved in claiming belonging to a presumably “extinct” ethnoracial category.     

Sea level,topography and island diversity: phylogeography of the Puerto Rican Red‐eyed Coquí, Eleutherodactylus antillensis

Quaternary climatic oscillations caused changes in sea level that altered the size, number and degree of isolation of islands, particularly in land‐bridge archipelagoes. Elucidating the demographic effects of these oscillations increases our understanding of the role of climate change in shaping evolutionary processes in archipelagoes. The Puerto Rican Bank (PRB) (Puerto Rico and the Eastern Islands, which comprise Vieques, Culebra, the Virgin Islands and associated islets) in the eastern Caribbean Sea periodically coalesced during glaciations and fragmented during interglacial periods of the quaternary. To explore population‐level consequences of sea level changes, we studied the phylogeography of the frog Eleutherodactylus antillensis across the archipelago. We tested hypotheses encompassing vicariance and dispersal narratives by sequencing mtDNA (c. 552 bp) of 285 individuals from 58 localities, and four nuDNA introns (totalling c. 1633 bp) from 173 of these individuals. We found low support for a hypothesis of divergence of the Eastern Islands populations prior to the start of the penultimate interglacial c. 250 kya, and higher support for a hypothesis of colonization of the Eastern Islands from sources in eastern Puerto Rico during the penultimate and last glacial period, when a land bridge united the PRB. The Río Grande de Loíza Basin in eastern Puerto Rico delineates a phylogeographic break. Haplotypes shared between the PRB and St. Croix (an island c. 105 km south‐east of this archipelago) likely represent human‐mediated introductions. Our findings illustrate how varying degrees of connectivity and isolation influence the evolution of tropical island organisms.     

Origin of the green iguana (Iguana iguana) invasion in the greater Caribbean Region and Fiji

Invasive populations of green iguanas (Iguanidae: Iguana iguana) are widely established beyond their native Central, South American, and Lesser Antillean range in various islands of the Pacific, Florida USA, and in the Greater Caribbean Region. Although widespread, information about these invasions is scarce. Here we determine the origin of invasive populations of green iguanas in Puerto Rico, Fiji, The Caymans, Florida USA, The Dominican Republic, the US Virgin Islands (USVI) of St. Thomas and St. Croix, and a U.S.A pet store. We sampled 120 individuals from these locations and sequenced one mitochondrial (ND4) and two nuclear (PAC and NT3) loci. We also include a preliminary characterization of population structure throughout Puerto Rico using six microsatellite loci to genotype individuals across 10 sampling sites. Comparing the genealogical relationships of all our samples to published sequencing data from the native range, we found that sampled populations were largely a product of populations from Colombia and El Salvador; two countries with multiple, industrial-size pet iguana farming operations. Notably, we found that haplotypes detected exclusively in the USVI and Puerto Rico’s outlying island of Vieques are closely linked to green iguanas native to Saba and Montserrat (Lesser Antilles); a clade not reported in the pet trade. Our population genetic analyses did not reveal isolation among sampling sites in Puerto Rico, rather the evidence supported admixture across the island. This study highlights the roles of the pet trade and lack of regulation in the spread of green iguanas beyond their native range.

     

New microsatellite markers for the ectomycorrhizal fungus Pisolithus tinctorius sensu stricto reveal the genetic structure of US and Puerto Rican populations

The ectomycorrhizal fungus Pisolithus tinctorius has been introduced to many areas around the world as a source of inoculum for pine plantations. However, little is known about the genetic structure of fungal populations in their introduced habitats. To study the genetics of exotic P. tinctorius populations, we developed and employed seven new microsatellite markers and compared samples from Puerto Rico (exotic range) and the eastern United States (native range). Bayesian cluster analysis, neighbor joining analysis and F_ST values all strongly separated Puerto Rican populations from North American populations. Consistent with a founder effect, populations from Puerto Rico had reduced allelic richness when compared to samples from the United States. The genetic structure of P. tinctorius populations in Puerto Rico is weak to modest and is not correlated with geographic distance reflecting anthropogenic movement of inoculum with forestry practices.     

Shell shape variation in the Nassariid Buccinanops globulosus in northern Patagonia

Morphological variation among natural populations is a phenomenon commonly observed in marine invertebrates and well studied, particularly, in shelled gastropods. The nassariid Buccinanops globulosus is interesting to study shell shape variation because it exhibits strong interpopulation differences in life history features, including maximum size, fecundity and growth rate. In this study, we examined the pattern of variation in size and shell shape among populations and between sexes of B. globulosus (Bahía San Antonio 40°29′S 63°01′W, Playa Villarino 40°45′S 64°40′W and Bahía Nueva 42°46′S 65°02′W). In particular, we used geometric morphometric techniques to test: (1) whether the two components of shell morphology (size and shape) are independent and (2) whether shape differences between sexes are consistently found among populations, regardless of their body sizes. Our results show shell shape variation between the populations of B. globulosus of northern Patagonia. Intra-specific shell shape variation is affected by body size, indicating allometry. Regardless of the size differences, individuals from Playa Villarino have high-spired shells, and shorter apertures and wider columellar area than individuals from the other populations. Also, sex-related shape differences were consistently found at each population, thus suggesting a common sexual dimorphism in shell morphology for this species. The functional significance of the variability found is discussed in terms of the flexibility of developmental programmes for morphology as well as the evolution of phenotypic plasticity.     

HISTORICAL BIOGEOGRAPHY OF THE BANANAQUIT (COEREBA FLAVEOLA) IN THE CARIBBEAN REGION: A MITOCHONDRIAL DNA ASSESSMENT

We analyzed mitochondrial DNA (mtDNA) restriction-site variation in bananaquit (Coereba flaveola; Aves, Coerebinae) populations sampled on 12 Caribbean islands and at 5 continental localities in Central America and northern South America. Multiple fixed restriction-site differences genetically defined several regional bananaquit populations. An mtDNA clade representing all Jamaican bananaquits was the most divergent; the estimated average sequence divergence (d_xy) between Jamaican and all other mtDNA haplotypes surveyed was 0.027. Three groups of populations, representing Central America, northern South America, and the eastern Antilles (Puerto Rico to Grenada) were nearly equally differentiated among themselves (average d_xy = 0.014), and may represent a single, recent range expansion. Within the eastern Antilles, three geographically restricted haplotype groups were identified: Puerto Rico, north-central Lesser Antilles (U.S. Virgin Islands to St. Lucia), and Grenada–St. Vincent. The evolutionary relationships of these groups were not clear. Genetic homogeneity of the island populations from the U.S. Virgin Islands to St. Lucia suggested a recent spread of a specific north-central Lesser Antillean haplotype through most of those islands. Haplotype variation across this region indicated that this spread may have occurred in two waves, first through the southernmost islands of St. Lucia, Martinique, and Dominica, and more recently from Guadeloupe to the north. The geographic distribution of mtDNA haplotypes, and of bananaquit populations, suggests periods of invasiveness followed by relative geographic quiescence. Although most genetic studies of bird populations have revealed homogeneity over large geographic areas, our findings provide a remarkable counterexample of strong geographic structuring of mtDNA variation over relatively small distances. Furthermore, although the mtDNA data were consistent with several subspecific distinctions, it was clear that named subspecies do not define equally differentiated evolutionary entities.     

Genetic structure of <Emphasis Type="Italic">Varroa destructor</Emphasis> populations infesting <Emphasis Type="Italic">Apis mellifera</Emphasis> colonies in Argentina

Although mitochondrial DNA mapping of Varroa destructor revealed the presence of several haplotypes, only two of them (Korean and Japanese haplotypes) were capable to infest Apis mellifera populations. Even though the Korean haplotype is the only one that has been reported in Argentina, these conclusions were based on mites sampled in apiaries from a specific geographical place (Buenos Aires province). To study mites from several sites of Argentina could reveal the presence of the Japanese genotype, especially considering sites near to Brazil, where Japanese haplotype was already detected. The aim of this work was to study the genetic structure of V. destructor populations from apiaries located in various provinces of Argentina, in order to determine the presence of different haplotypes. The study was carried out between January 2006 and December 2009. Phoretic adult Varroa mites were collected from honey bee workers sampled from colonies of A. mellifera located in Entre Ríos, Buenos Aires, Corrientes, Río Negro, Santa Cruz and Neuquén provinces. Twenty female mites from each sampling site were used to carry out the genetic analysis. For DNA extraction a nondestructive method was used. DNA sequences were compared to Korean haplotype (AF106899) and Japanese haplotype (AF106897). All DNA sequences obtained from mite populations sampled in Argentina, share 98% of similitude with Korean Haplotype (AF106899). Taking into account these results, we are able to conclude that Korean haplotype is cosmopolite in Argentina.     

Latitudinal variations of the yield and quality of agar from <Emphasis Type="Italic">Gelidium robustum</Emphasis> (Gelidiales,Rhodophyta) from the main commercial harvest beds along the western coast of the Baja California Peninsula,Mexico

The yield and quality of agar from Gelidium robustum from the main commercial harvest beds along the western coast of the Baja California Peninsula (Mexico) were evaluated within a latitudinal range of about 800 km (31°47′N to 27°05′N). Samples from six locations, Bahía Todos Santos, El Rosario, Isla de Cedros, Islas San Benito, Punta Eugenia, and Bahía Asunción, were analyzed. Bryozoan, protein, and agar content in the seaweed were estimated. The agar quality was determined by the content of 3,6-anhydrogalactose, sulfate, gel strength, and gelling and melting temperature. All the values of these variables were correlated and then with the satellite-derived data of the sea surface temperature (SST), net primary production (NPP), and photosynthetic active radiation (PAR) measured at each harvest bed during the summer months (June, July, and August) of 2000. In the northern and central region, the agar yield was 35% to 37% (Bahía Todos Santos, El Rosario, Isla de Cedros, and Islas San Benito), whereas lower yields were obtained from the southern beds (Punta Eugenia and Bahía Asunción). In contrast, the agar quality increased from the northern to the southern beds. A lower gel strength was obtained from Bahía Todos Santos and El Rosario (268 ± 16 and 205 ± 5 gcm⁻²) with a higher gel strength obtained from Isla de Cedros, Islas San Benito, and Bahía Asunción (384 to 444 ± 25 gcm⁻²). Yield was not correlated with the bryozoan content but was inversely correlated with the protein content in the seaweed. The sulfate content in the agar was inversely correlated with the gel strength and with the melting temperature. The 3,6-anhydrogalactose content showed slight variations among harvested beds. Analysis of satellite-derived data showed an equatorward increase of the SST, NPP, and PAR. The agar content correlated inversely with the equatorward increase of the NPP, whereas agar quality, i.e., gel strength, correlated positively with the NPP and PAR. No significant effects were observed on the yield and quality of agar with the latitudinal change of the SST.     

A polytene chromosome study of four populations of Anopheles aquasalis from Venezuela.

Polytene chromosome studies were undertaken to elucidate taxonomic relationships among populations of Anopheles aquasalis and A. emilianus in Venezuela. Four collection sites were chosen: two in Sucre state (Santa Fe and Guayana) where A. aquasalis (considered to be A. emilianus by Gabaldón and Escalante) is presumed to be the major regional vector of Plasmodium vivax; and two in areas where no malaria transmission occurs (Ca?o Rico, Aragua state, and Puerto Cabello, Carabobo state). The chromosome banding pattern of the four populations was identical and conformed to the standard chromosome map of A. aquasalis from Brazil. These results suggest that the population from Santa Fe and Guayana, considered to be A. emilianus, is conspecific with A. aquasalis. However, its status as a distinct species with a homosequential polytene chromosome banding pattern cannot be ruled out.     

Evaluation of the eradication program forAmblyomma variegatum (Acari: Ixodidae) on Puerto Rico

A cooperative effort between the United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services, the Agricultural Research Service, and the Department of Agriculture, Commonwealth Government of Puerto Rico has been successful in eardicatingAmblyomma variegatum (Fabricius) from the islands of Puerto Rico and Vieques (an island municipality of Puerto Rico). Application of acaricides to livestock and dogs at 14-day intervals for an 18-month period eliminated foci of tick infestation on 188 farms in four different locations without additional aerial or ground treatment. Reasons for the success and some of the costs associated with the eradication program on Puerto Rico are presented.     

Climate as a driver of tropical insular diversity: comparative phylogeography of two ecologically distinctive frogs in Puerto Rico

The effects of late Quaternary climate on distributions and evolutionary dynamics of insular species are poorly understood in most tropical archipelagoes. We used ecological niche models under past and current climate to derive hypotheses regarding how stable climatic conditions shaped genetic diversity in two ecologically distinctive frogs in Puerto Rico. Whereas the mountain coquí Eleutherodactylus portoricensis is restricted to montane forest in the Cayey and Luquillo Mountains, the red‐eyed coquí E. antillensis is a habitat generalist distributed across the entire Puerto Rican Bank (Puerto Rico and the Virgin Islands, excluding St Croix). To test our hypotheses, we conducted phylogeographic and population genetic analyses based on mitochondrial and nuclear loci of each species across their range in Puerto Rico. Patterns of population differentiation in E. portoricensis, but not in E. antillensis, supported our hypotheses. For E. portoricensis, these patterns include: individuals isolated by long‐term unsuitable climate in the Río Grande de Loíza Basin in eastern Puerto Rico belong to different genetic clusters; past and current climate strongly predicted genetic differentiation; and Cayey and Luquillo Mountains populations split prior to the last interglacial. For E. antillensis, these patterns include: genetic clusters did not fully correspond to predicted long‐term unsuitable climate; and past and current climate weakly predicted patterns of genetic differentiation. Genetic signatures in E. antillensis are consistent with a recent range expansion into western Puerto Rico, possibly resulting from climate change and anthropogenic influences. As predicted, regions with a large area of long‐term suitable climate were associated with higher genetic diversity in both species, suggesting larger and more stable populations. Finally, we discussed the implications of our findings for developing evidence‐based management decisions for E. portoricensis, a taxon of special concern. Our findings illustrate the role of persistent suitable climatic conditions in promoting the persistence and diversification of tropical island organisms.     

Using population genetics and demographic reconstruction to predict outcomes of genetic rescue for an endangered songbird

Genetic rescue can be a successful way to restore species genetic diversity, but it can also lead to outbreeding depression (decreases in hybrid fitness) if attempted in incompatible populations. Thus, population genetic profiles and demographic history are needed to evaluate the feasibility of translocation. We used population genetic analyses and Approximate Bayesian Computation (ABC) to assess genetic rescue as an option for two populations of the yellow-shouldered blackbird (Agelaius xanthomus), an endangered Puerto Rico endemic. The candidate recipient population, a managed population in Pitahaya (southwestern Puerto Rico), had been characterized previously for its mating system and population genetics. Here, we used nine microsatellite loci to measure the genetic diversity of a candidate source population, a subspecies (A. x. monensis) on Mona Island, 66 km west of Puerto Rico. We compared genetic diversity and inferred historical and contemporary gene flow between the two populations. We found clear population structure and no migration between populations, as well as evidence that the Mona population descended from the Pitahaya population approximately 95 generations ago. Despite the historical gene flow, the degree of contemporary genetic and environmental divergence means the Mona population may not be suitable for immediate use as a source population. We recommend (a) further investigating whether the observed population structure is due to adaptive or neutral forces, (b) testing the Mona population for behavioral plasticity in different environments, and (c) evaluating other source populations in addition to the Mona population for genetic rescue.     

Climatic stability and genetic divergence in the tropical insular lizard Anolis krugi,the Puerto Rican ‘Lagartijo Jardinero de la Montaña’

Two factors that can lead to geographic structuring in conspecific populations are barriers to dispersal and climatic stability. Populations that occur in different physiographic regions may be restricted to those areas by physical and/or ecological barriers, which may facilitate the formation of phylogeographic clades. Long‐term climatic stability can also promote genetic diversification, because new clades are more likely to evolve in areas that experience lesser climatic shifts. We conducted a phylogeographic study of the Puerto Rican lizard Anolis krugi to assess whether populations of this anole show genetic discontinuities across the species’ range, and if they do, whether these breaks coincide with the boundaries of the five physiographic regions of Puerto Rico. We also assessed whether interpopulation genetic distances in A. krugi are positively correlated with relative climatic stability in the island. Anolis krugi exhibits genetic structuring, but the phylogroups do not correspond to the physiographic regions of Puerto Rico. We used climatic reconstructions of two environmental extremes of the Quaternary period, the present conditions and those during the last glacial maximum (LGM), to quantify the degree of climatic stability between sampling locations. We documented positive correlations between genetic distances and relative climatic stability, although these associations were not significant when corrected for autocorrelation. Principal component analyses indicated the existence of climatic niche differences between some phylogeographic clades of A. krugi. The approach that we employed to assess the relationship between climatic stability and the genetic architecture of A. krugi can also be used to investigate the impact of factors such as the spatial distribution of food sources, parasites, predators or competitors on the genetic landscape of a species.     

Phylogeography of an Island endemic, the Puerto Rican Freshwater Crab (Epilobocera sinuatifrons)

The endemic Puerto Rican crab, Epilobocera sinuatifrons (Pseudothelphusidae), has a freshwater-dependant life-history strategy, although the species has some capabilities for terrestrial movement as adults. In contrast to all other freshwater decapods on the island (e.g., caridean shrimp), E. sinuatifrons does not undertake amphidromous migration, and is restricted to purely freshwater habitats and adjacent riparian zones. As Puerto Rico has a dynamic geologic history, we predicted that both the life history of E. sinuatifrons and the geological history of the island would be important determinants of phylogeographic structuring in the species. Using a fragment of the cytochrome c oxidase subunit 1 mtDNA (mitochondrial DNA) gene, we tested for deviations from panmixia among and within rivers draining Puerto Rico and used statistical phylogeography to explore processes that may explain extant patterns of genetic variation in the species. While populations of E. sinuatifrons were significantly differentiated among rivers, they were likely to be recently derived because nested clade analysis (NCA) indicated evolutionarily recent restricted gene flow with isolation by distance (IBD) and contiguous range expansion at various spatial scales. Ongoing drainage rearrangements associated with faulting and land slippage were invoked as processes involved in sporadic gene flow among rivers throughout the Pleistocene. Patterns of genetic differentiation conformed to IBD and population demographic statistics were nonsignificant, indicating that although recently derived, populations from different rivers were in drift-mutation equilibrium. A shallow (0.6 million years ago), paraphyletic split was observed in the haplotype network, which NCA indicated arose via allopatric fragmentation. This split coincides with an area of high relief in central Puerto Rico that may have experienced relatively little drainage rearrangements. Shallow but significant genetic isolation of populations of E. sinuatifrons among Puerto Rican rivers suggests phylogeographic patterns that are intermediate to terrestrial habitat specialists (highly divergent populations) and other freshwater biota, such as amphidromous species and insects with aerial adult dispersal (highly connected populations).     

Chemico-nutritional composition of meat of Strombus galeatus (Mesogastropoda: Strombidae)]

Strombus galeatus samples were collected in Lagarto (10 degrees 06'N,85 degrees 48'W), Bahía Ballena (9 degrees 42'N,85 degrees 01'W) and Golfito (8 degrees 30'N,83 degrees 10'W) at the Pacific coast of Costa Rica. Individual weight ranged between 141.9 and 241.3 g (41.3-65.6% edible). Over 72% is water, 23% protein and 3% ash. The caloric content varied between 126.5 and 129 kcal/100g. Fat, crude fiber and carbohydrates contents were small. Mean ranges (%) in minerals were: 403.0-465 P, 233.5-315.7 Ca, 89.7-315.0 K, 122.3-145.5 Na, 217.5-266.3 Mg, 1.5-5.3 Fe, 2.0-8.7 Zn and 0.2-0.5 mg % Cu. As was not detected, and the Cd and Pb contents were 0.046-0.062 and 0.19-0.21 mg/kg, respectively. Concentrations of heavy metals in the meat are not toxic for humans.     

Preliminary genetic data on some Caribbean Artemia franciscana strains based on RAPD's

A total of fourteen Artemia samples from Colombia, Venezuela, Curaçao (Netherlands Antilles), Puerto Rico, and reference samples from U.S.A. (San Francisco Bay, SFB) belonging to the superspecies Artemia franciscana, and Argentina (A. persimilis), were analysed with the RAPD technique in order to demonstrate genetic dissimilarities. Pearson's correlation coefficients between the DNA banding patterns were calculated. They served as input values for the construction of UPGMA dendrograms. The results indicate that, within the collection of Colombian, Venezuelan and the two Netherlands Antilles Artemiacyst samples examined, two different groups seem to exist. Geographically, the mountainous area of Sierra Nevada de Santa Marta separates these two groups (lower Caribbean to the South and middle Caribbean to the North). Although the Caribbean, North and South American populations belong to A. franciscana, genetic discontinuities are to be expected due to habitat differences and geographic isolation. The Sierra Nevada (with an altitude of about 5800 m) emerges as the barrier very likely to explain the observed RAPD differences. Little genetic variability was present in the Colombian samples from Manaure that were collected almost every ten years, nor in the samples from Galerazamba collected almost two decades apart, although these samples were more likely subjected to different prevailing environmental conditions. The SFB population did not show a very close relation with all Caribbean populations analyzed, including the Puerto Rican. All A. franciscana populations analyzed were divergent from A. persimilis(Argentina).     

Reconstructing population history using JC virus: Amerinds, Spanish, and Africans in the ancestry of modern Puerto Ricans.

The roots of the Hispanic populations of the Caribbean Islands and Central and South America go back to three continents of the Old World. In Puerto Rico major genetic contributions have come from (1) Asians in the form of the aboriginal Taino population, an Arawak tribe, present when Columbus arrived on the Island, (2) Europeans, largely Spanish explorers, settlers, government administrators, and soldiers, and (3) Africans who came as part of the slave trade. Since JC virus (JCV) genotypes characteristic of Asia, Europe, and Africa have been identified, and excretion of JCV in urine has been proposed as a marker for human migrations, we sought to characterize the JCV strains present in a Caribbean Hispanic population. We found that the strains of JCV present today in Puerto Rico are those derived from the Old World populations represented there: Types 1B and 4 from Spain, Types 3A, 3B, and 6 from Africa, and Type 2A from Asia. The Type 2A genotype represents the indigenous Taino people. This JCV genotype was represented much more frequently (61%) than would be predicted by the trihybrid model of genetic admixture. This might be attributable to characteristics of JCV Type 2A itself, as well as to the nature of the early relationships between Spanish men and native women. These findings indicate that the JCV strains carried by the Taino Indians can be found in today's Puerto Rican population despite the apparent demise of these people more than two centuries ago. Therefore, molecular characterization of JCV provides a tool to supplement genetic techniques for reconstructing population histories including admixed populations.