Joana Micael

Dissemination of antibiotic resistant Enterococcus spp. and Escherichia coli from wild birds of Azores Archipelago

Antibiotic-resistant is profoundly important to human and animal health, but the environmental reservoirs of resistance determinants are poorly understood, in particular in wild environments in remote Archipelagos. Moreover, the prevalence of antibiotic-resistant bacteria in wild bird populations is rather unknown. In the present study, we used the Azores Islands as a model study for antimicrobial resistance in a remote Archipelago, and examined the antibiotic resistance profile in enterococci and Escherichia coli recovered from faecal samples of wild birds collected in this Archipelago. A total of 138 enterococci and 115 E. coli isolates were analyzed for resistance to antimicrobial agents. Of the enterococcal isolates, Enterococcus faecalis was the most prevalent detected species (59 isolates), followed by Enterococcus faecium (40 isolates), Enterococcus durans (27 isolates) and Enterococcus hirae (12 isolates). The enterococci strains showed high percentages of resistance to tetracycline (32.6%), to ciprofloxacin (19.6%) and to erythromycin (11.6%). Lower level of resistance (<10%) was detected for ampicillin, chloramphenicol and teicoplanin. One vancomycin-resistant E. faecalis isolate was detected and harbored the vanA resistant gene. Resistance genes detected included tet(M) and/or tet(L), ermB in all tetracycline and erythromycin-resistant isolates. Resistance in E. coli isolates was detected for ampicillin, tetracycline, sulfamethoxazole/trimethoprim, streptomycin, and tobramycin. The blaTEM, aadA, aadA5, strA, strB, tet(A) and/or tet(B), and the intI genes were found in all ampicillin, streptomycin, tetracycline, and sulfamethoxazole/trimethoprim-resistant isolates respectively. The data shown in this study are essential to improve knowledge about the dissemination of resistant strains through wild birds from remote archipelagos such as the Azores Archipelago and the possible implications involved in transferring these resistances either to other animals or to humans.

Diversification within glacial refugia: tempo and mode of evolution of the polytypic fish Barbus sclateri

A diversity of evolutionary processes can be responsible for generating and maintaining biodiversity. Molecular markers were used to investigate the influence of Plio‐Pleistocene climatic oscillations on the evolutionary history of taxa restricted to the freshwaters of a classical glacial refugium. Population genetic, phylogenetic and phylogeographical methods allowed the inference of temporal dynamics of cladogenesis and processes shaping present‐day genetic constitution of Barbus sclateri, a polytypic taxon found in several independent river drainages in southern Iberian Peninsula. Results from different analyses consistently indicate several range expansions, high levels of allopatric fragmentation, and admixture following secondary contacts throughout its evolutionary history. Using a Bayesian demographical coalescent model on mitochondrial DNA sequences calibrated with fossil evidence, all cladogenetic events within B. sclateri are inferred to have occurred during the Pleistocene and were probably driven by environmental factors. Our results suggest that glaciation cycles did not inhibit cladogenesis and probably interacted with regional geomorphology to promote diversification. We conclude that this polytypic taxon is a species complex that recently diversified in allopatry, and that Pleistocene glaciation–deglaciation cycles probably contributed to the generation of biological diversity in a classical glacial refugium with high endemicity.

Allocation of nutrients during the reproductive cycle of Ophidiaster ophidianus (Echinodermata: Asteroidea)

The reproductive cycle of Ophidiaster ophidianus (strictly protected status) from São Miguel Island, in the Azorean Archipelago was studied. The reproductive strategy; the energy allocation of each sex during the reproductive cycle and the nutritional condition of the population were analyzed. Gonadal index (GI) showed a clear seasonal pattern with spawning between August and October but histological examination revealed that gamete release can occur throughout the entire year. The pyloric caeca index (PCI) showed little annual variation but with an inverse relationship with the GI. Allocation of energy to the gonads and to the pyloric caeca reflected the seasonal reproductive strategy of this species. Individuals were able to simultaneously develop gonads, pyloric caeca, and quickly regenerate lost arms. There was a major expenditure of energy by females compared to males but, sexual size dimorphism was not observed. The reproductive pattern observed in O. ophidianus combining rich food availability and seawater temperatures characteristic of a temperate zone may be the key to the success of this species in the Azorean oceanic Island.

The global invader Paracerceis sculpta (Isopoda: Sphaeromatidae) has extended its range to the Azores Archipelago

The occurrence of Paracerceis sculpta (Holmes, 1904) in the Macaronesia biogeographical region is reported for the first time. This isopod, native from the northeastern Pacific region, has probably been transported as hull fouling, hiding in either niche areas of vessels or associated with fouling bryozoans. Specimens of P. sculpta were collected from bryozoans or other fouling organisms colonizing the marina structures. From the three distinct sexually mature male morphs of P. sculpta, only the larger was found, confirming the absence of the two smaller male morphs in an introduced population. Paracerceis sculpta is the first non-indigenous marine isopod reported in the Azores Archipelago. Environmental impacts on non-indigenous areas for this isopod are unknown; nevertheless, the occurrence of P. sculpta in the Azores Archipelago corresponds to the link between both sides of the Atlantic Ocean and is evidence of the ongoing processes of biotic homogenization of marine communities on a global scale.

Diversity of shallow-water asteroids (Echinodermata) in the Azorean Archipelago

A comprehensive review of the literature on shallow-water asteroids (Echinodermata) recorded in Azores was carried out to establish a definitive list for the Archipelago. A total of 49 echinoderm species was compiled, comprising members of all extant classes; Crinoidea (1), Asteroidea (12), Ophiuroidea (11), Echinoidea (10) and Holothuroidea (7). References of asteroids occurence in the Azores, including historical records and distribution of asteroids from the Azores are given. Seven asteroid species recorded found in the Azores are found also in the Mediterranean and adjoining Atlantic coastlines, three are recorded from the Mediterranean and both sides of the Atlantic, one is limited to the Eastern Atlantic and one is circumtropical. Differences between the littoral hydrological conditions found on the North American coast and those in Azores makes the colonization from American coasts particularly difficult and probably are related to chance events like the episodic anomalies found in the general pattern of oceanic circulation. Asteroids are important in determining habitat structure for other species and can represent a substantial portion of the ecosystem biomass.

Geographic Information System in a Multi-Criteria Tool for Mariculture Site Selection

The continuous growth in fish consumption and related activities is stressing the fishing industry worldwide. To counteract this, mariculture might represent an opportunity for consumers, industry and marine resource sustainability, as long as careful site selection is taken into consideration. The current study was developed to assess potential sites for the implementation of marine fish-cage industries on the Azores Archipelago (North Atlantic), through the application of a multi-criteria approach based on geographic information. Descriptors that may have either direct or indirect influences on the development of mariculture activity in the Açores were discriminated into factors and constraints and grouped into environmental, socioeconomic, and administrative categories. Factors were weighted and data integrated using geographic information system (GIS) methods. Suitability maps were generated and a total area of 17.7 km2 was identified as suitable for mariculture in São Miguel Island, segmented into different option levels. This multiple criteria approach provides the information necessary for stakeholders to realize the effects of each descriptor in possible implementation sites for mariculture. This will be a useful tool to improve environmental planning, management and decision-making for mariculture activities.

Genetic and morphometric diversity of the goldcrest (Regulus regulus) populations in the Azores

We studied the genetic diversity and phylogeography of the goldcrest Regulus regulus from the archipelago of the Azores (North Atlantic Ocean) based on sequences of two mitochondrial genes (cytochrome b and the NADH dehydrogenase subunit 2) and one nuclear gene in the Z-chromosome (intron 9 of the aconitase 1) from 69 individuals, and 41 birds from the Canary Islands and continental Europe for outgroup comparison. To understand the level of concordance between the genetic data and possible morphometric variability, 197 adult living birds from the seven Azorean islands where the species breeds were analysed in terms of eight morphometric characters. Our results are in accordance with previous studies, indicating a recent expansion of goldcrests throughout the archipelago and a low divergence in relation to continental Europe. Within the Azores, there is evidence of historical and/or recent gene flow among the islands populations, revealing a lack of current genetic structure within the archipelago. Only goldcrests from Flores Island seem to be genetically distinct and showed significantly larger body mass and tarsus length than birds on the other islands.

The non-indigenous Schizoporella errata (Bryozoa: Cheilostomatida) introduced into the Azores Archipelago

The bryozoan Schizoporella errata was found in the waters of the island of Sao Miguel (Azores, Portugal) in August 2013. Its occurrence in the Ponta Delgada Marina suggested that it had been newly introduced into the area, probably via maritime traffic, owing to the fouling proclivity of these cheilostome colonies. It may be expected that S. errata will disperse throughout the Azores Archipelago, being transported by recreational boating as a fouling component of hulls. Measures to minimize a rapid spread of the species should be addressed and the effects of its presence on the native community studied.

Some Bryozoa species recently introduced into the Azores: reproductive strategies as a proxy for further spread

In the marine environment, control of invasive species’ population levels, that is, keeping them at an abundance level which is below a density-dependent adverse effect, may be the most attainable goal for the management of introduced bryozoans. An improved understanding of reproductive strategies and life history traits is key in order to understand the spreading potential. The assessment of the magnitude and temporal dynamics of propagule pressure from the reproducing population important for the success of control actions and needs is to be determined prior to any field intervention. The reproductive cycle of three fouling bryozoans (Bugula neritina, Tricellaria inopinata and Virididentula dentata) in the waters of the Azores Archipelago was assessed. The study revealed that although the release of larvae can occur throughout the entire year, its intensity and developmental and the attachment success of the ancestrula are not even throughout the year and that each species’ reproductive development needs to be determine independently. In the light of these findings, it is possible to determine the best time to apply field actions aimed at controlling invasive population’s density levels, optimizing the always scarce financial resources for marine management.

Caprella scaura Templeton, 1836: an invasive caprellid new to the Azores archipelago

The present study reports for the first time the occurrence of Caprella scaura in the remote oceanic islands of the Azores archipelago. Caprella scaura is a widespread caprellid with an invasive potential and a complicated taxonomy due to the existence of individuals that vary morphologically between and within regions. Caprella scaura specimens collected in this study were assigned to subspecies C. s. scaura and C. s. typica, supporting already published evidence that these two names should be synonymized into a single subspecies. Previous C. scaura records were also analyzed in order to provide a more updated insight on current C. s. scaura distribution. The year-round presence of a breeding population in the Ponta Delgada marina suggests that C. scaura is locally well-established. Recent C. scaura presence in a marina and its association with non-native fouling bryozoans suggest that the most probable introduction vector in the Azores is through hull fouling.