Alnilam Research and Conservation

Hoyo de Manzanares, Spain

Alnilam Research and Conservation

Hoyo de Manzanares, Spain
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Canadas A.,ALNILAM Research and Conservation | Vazquez J.A.,ALNILAM Research and Conservation
Deep-Sea Research Part II: Topical Studies in Oceanography | Year: 2017

The short-beaked common dolphin Mediterranean subpopulation appears to have suffered a steep decline over recent decades and was listed in 2003 as 'Endangered' in the IUCN Red List of Threatened Species. The Alboran Sea is the last region in the Mediterranean where it is still abundant. In this study, we relate features of this species' ecology to climate change, focusing on distribution and density. This work used a two decades-long dataset on the common dolphin in the Alboran Sea and a time series of environmental changes. Once established, these relationships were used in conjunction with some simulated scenarios of environmental change to predict the potential effects of further change on these species over the next 100 years. Two approaches were used: 1) projection from a regression line from local variation, and 2) a HadCM3 climate model with time-varying anthropogenic effects. Generalized Additive Models were used to model the relationship between density of the animals with SST and other environmental covariates. Results from both approaches were very similar. The predictions of density from the regression line fell within the ranges from the HadCM3 climate model, the first being based on local and locally, point to point, differentiated information, which lead us to consider the first approach as the best for this area. At the small spatial scale of the Alboran Sea and Gulf of Vera, an increase in SST will potentially yield a reduction in suitable habitat for common dolphins, with a progressive reduction in density from east to west. © 2017 Elsevier Ltd.

Gimenez J.,Estacion Biologica de Donana Consejo Superior de Investigaciones Cientificas EBD CSIC | Canadas A.,Alnilam Research and Conservation | Ramirez F.,Estacion Biologica de Donana Consejo Superior de Investigaciones Cientificas EBD CSIC | Afan I.,SIG | And 3 more authors.
Marine Ecology Progress Series | Year: 2017

Community structure and functioning is shaped by resource partitioning between cooccurring species. Niche differentiation among sympatric species can be reached through trophic, spatial or temporal segregation to avoid competitive exclusion. Intraspecific segregation in the use of habitats and resources might determine, in turn, a population's niche width and interspecific segregation. The Alboran Sea is the only area in the Mediterranean where common and striped dolphins coexist abundantly. Therefore, these putative competing species provided the opportunity to investigate niche partitioning through spatial modelling and trophic analysis. Density surface modelling and nitrogen and carbon stable isotopes (δ15N and δ13C) were used to investigate spatial and trophic niche partitioning at inter-and intraspecific levels. The 2 species showed high isotopic overlap. However, we could not rule out the possibility of interspecific trophic segregation, as isotopic similarity does not necessarily mean true ecological or dietary similarity. Among conspecifics, variations in δ15N and δ13C values with dolphin length pointed to ontogenetic dietary changes in striped dolphins, while sex played only a minor role in δ13C values. Spatially, these species tended to segregate their core areas of distribution, with common dolphins being more coastal than striped dolphins, which occupied adjacent, deeper waters. Overall, the main enabler for the coexistence of common and striped dolphins in the Alboran Sea was spatial segregation. © 2017 Inter-Research.

Rogan E.,University College Cork | Canadas A.,ALNILAM Research and Conservation | Macleod K.,Andrews University | Santos M.B.,Spanish Institute of Oceanography | And 5 more authors.
Deep-Sea Research Part II: Topical Studies in Oceanography | Year: 2017

In spite of their oceanic habitat, deep diving cetacean species have been found to be affected by anthropogenic activities, with potential population impacts of high intensity sounds generated by naval research and oil prospecting receiving the most attention. Improving the knowledge of the distribution and abundance of this poorly known group is an essential prerequisite to inform mitigation strategies seeking to minimize their spatial and temporal overlap with human activities. We provide for the first time abundance estimates for five deep diving cetacean species (sperm whale, long-finned pilot whale, northern bottlenose whale, Cuvier's beaked whale and Sowerby's beaked whale) using data from three dedicated cetacean sighting surveys that covered the oceanic and shelf waters of the North-East Atlantic. Density surface modelling was used to obtain model-based estimates of abundance and to explore the physical and biological characteristics of the habitat used by these species. Distribution of all species was found to be significantly related to depth, distance from the 2000m depth contour, the contour index (a measure of variability in the seabed) and sea surface temperature. Predicted distribution maps also suggest that there is little spatial overlap between these species. Our results represent the best abundance estimates for deep-diving whales in the North-East Atlantic, predict areas of high density during summer and constitute important baseline information to guide future risk assessments of human activities on these species, evaluate potential spatial and temporal trends and inform EU Directives and future conservation efforts. © 2017.

Panigada S.,Tethys Research Institute | Lauriano G.,European Commission - Joint Research Center Ispra | Donovan G.,The International Whaling Commission | Pierantonio N.,Tethys Research Institute | And 3 more authors.
Deep-Sea Research Part II: Topical Studies in Oceanography | Year: 2017

Systematic, effective monitoring of animal population parameters underpins successful conservation strategy and wildlife management, but it is often neglected in many regions, including much of the Mediterranean Sea. Nonetheless, a series of systematic multispecies aerial surveys was carried out in the seas around Italy to gather important baseline information on cetacean occurrence, distribution and abundance. The monitored areas included the Pelagos Sanctuary, the Tyrrhenian Sea, portions of the Seas of Corsica and Sardinia, the Ionian Seas as well as the Gulf of Taranto. Overall, approximately 48,000km were flown in either spring, summer and winter between 2009-2014, covering an area of 444,621km2. The most commonly observed species were the striped dolphin and the fin whale, with 975 and 83 recorded sightings, respectively. Other sighted cetacean species were the common bottlenose dolphin, the Risso's dolphin, the sperm whale, the pilot whale and the Cuvier's beaked whale. Uncorrected model- and design-based estimates of density and abundance for striped dolphins and fin whales were produced, resulting in a best estimate (model-based) of around 95,000 striped dolphins (CV=11.6%; 95% CI=92,900-120,300) occurring in the Pelagos Sanctuary, Central Tyrrhenian and Western Seas of Corsica and Sardinia combined area in summer 2010. Estimates were also obtained for each individual study region and year. An initial attempt to estimate perception bias for striped dolphins is also provided. The preferred summer 2010 uncorrected best estimate (design-based) for the same areas for fin whales was around 665 (CV=33.1%; 95% CI=350-1260). Estimates are also provided for the individual study regions and years. The results represent baseline data to develop efficient, long-term, systematic monitoring programmes, essential to evaluate trends, as required by a number of national and international frameworks, and stress the need to ensure that surveys are undertaken regularly and at a sufficient spatial scale. The management implications of the results are discussed also in light of a possible decline of fin whales abundance over the period from the mid-1990s to the present. Further work to understand changes in distribution and to allow for improved spatial models is emphasized. © 2017 Elsevier Ltd.

Lauriano G.,European Commission - Joint Research Center Ispra | Pierantonio N.,Tethys Research Institute | Kell L.,ICCAT Secretariat | Canadas A.,Alnilam Research and Conservation | And 3 more authors.
Deep-Sea Research Part II: Topical Studies in Oceanography | Year: 2015

Fishery-independent surface density and abundance estimates for the swordfish were obtained through aerial surveys carried out over a large portion of the Central Mediterranean, implementing distance sampling methodologies. Both design- and model-based abundance and density showed an uneven occurrence of the species throughout the study area, with clusters of higher density occurring near converging fronts, strong thermoclines and/or underwater features. The surface abundance was estimated for the Pelagos Sanctuary for Mediterranean Marine Mammals in the summer of 2009 (n=1152; 95%CI=669.0-1981.0; %CV=27.64), the Sea of Sardinia, the Pelagos Sanctuary and the Central Tyrrhenian Sea for the summer of 2010 (n=3401; 95%CI=2067.0-5596.0; %CV=25.51), and for the Southern Tyrrhenian Sea during the winter months of 2010-2011 ( n=1228; 95%CI=578-2605; %CV=38.59). The Mediterranean swordfish stock deserves special attention in light of the heavy fishing pressures. Furthermore, the unreliability of fishery-related data has, to date, hampered our ability to effectively inform long-term conservation in the Mediterranean Region. Considering that the European countries have committed to protect the resources and all the marine-related economic and social dynamics upon which they depend, the information presented here constitute useful data towards the international legal requirements under the Marine Strategy Framework Directory, the Common Fisheries Policy, the Habitats and Species Directive and the Directive on Maritime Spatial Planning, among the others. © 2017 Elsevier Ltd.

Druon J.-N.,European Commission - Joint Research Center Ispra | Panigada S.,Tethys Research Institute | David L.,EcoOcean Institute | Gannier A.,British Petroleum | And 7 more authors.
Marine Ecology Progress Series | Year: 2012

The development of synoptic tools is required to derive the potential habitat of fin whales Balaenoptera physalus on a large-scale basis in the Mediterranean Sea, as the species has a largely unknown distribution and is at high risk of ship strike. We propose a foraging habitat model for fin whales in the western Mediterranean Sea relying on species ecology for the choice of predictors. The selected environmental variables are direct predictors and resource predictors available at daily and basin scales. Feeding habitat was determined mainly from the simultaneous occurrence of large oceanic fronts of satellite-derived sea-surface chlorophyll content (chl a) and temperature (SST). A specific range of surface chl a content (0.11 to 0.39 mg m-3) and a minimum water depth (92 m) were also identified to be important regional criteria. Daily maps were calibrated and evaluated against independent sets of fin whale sightings (presence data only). Specific chl a fronts represented the main predictor of feeding environment; therefore, derived habitat is a potential, rather than effective, habitat, but is functionally linked to a proxy of its resource (chl a production of fronts). The model performs well, with 80% of the presence data <9.7 km from the predicted potential habitat. The computed monthly, seasonal and annual maps of potential feeding habitat from 2000 to 2010 correlate, for the most part, with current knowledge on fin whale ecology. Overall, fin whale potential habitat occurs frequently during summer in dynamic areas of the general circulation, and is substantially more spread over the basin in winter. However, the results also displayed high year-to-year variations (40 to 50%), which are essential to consider when assessing migration patterns and recommending protection and conservation measures. © Inter-Research 2012.

Wierucka K.,Information and Research on Cetaceans | Verborgh P.,Information and Research on Cetaceans | Meade R.,Information and Research on Cetaceans | Colmant L.,Information and Research on Cetaceans | And 4 more authors.
Marine Ecology Progress Series | Year: 2014

Long-finned pilot whales Globicephala melas are a commonly encountered species in the Mediterranean Sea. In 2006-2007, an outbreak of the dolphin morbillivirus in the Western Mediterranean resulted in increased mortality of this species. The aim of this study was to determine whether survival rates differed between clusters of Spanish Medi - terranean pilot whales, and how the epizootic in - fluenced these survival rates. Photo-identification surveys were conducted between 1992 and 2009. Association indices were used to define clusters of individuals that associate with each other more frequently than with others. Based on a Cormack-Jolly- Seber survival rate model, apparent survival rate estimates varied from 0.821 to 0.995 over 11 clusters for the 1992-2009 period. When the effect of the morbillivirus outbreak was modeled, 3 clusters with distinctly lower survival rates from previous models presented lower estimates after the outbreak (survival rate dropped from 0.919 [95% CI: 0.854-0.956] to 0.547 [95% CI: 0.185-0.866]), suggesting a negative influence of the epizootic or other unknown additive factors on certain clusters. This information is critical for the conservation of long-finned pilot whales, since they are listed as 'data deficient' in the Mediterranean Sea by the IUCN and as 'vulnerable' in the Spanish National Catalogue of Endangered Species. © Inter-Research 2014.

De Stephanis R.,CSIC - Doñana Biological Station | Gimenez J.,CSIC - Doñana Biological Station | Carpinelli E.,Information and Research on Cetaceans | Gutierrez-Exposito C.,CSIC - Doñana Biological Station | Canadas A.,Alnilam Research and Conservation
Marine Pollution Bulletin | Year: 2013

Marine debris has been found in marine animals since the early 20th century, but little is known about the impacts of the ingestion of debris in large marine mammals. In this study we describe a case of mortality of a sperm whale related to the ingestion of large amounts of marine debris in the Mediterranean Sea (4th published case worldwide to our knowledge), and discuss it within the context of the spatial distribution of the species and the presence of anthropogenic activities in the area that could be the source of the plastic debris found inside the sperm whale. The spatial distribution modelled for the species in the region shows that these animals can be seen in two distinct areas: near the waters of Almería, Granada and Murcia and in waters near the Strait of Gibraltar. The results shows how these animals feed in waters near an area completely flooded by the greenhouse industry, making them vulnerable to its waste products if adequate treatment of this industry's debris is not in place. Most types of these plastic materials have been found in the individual examined and cause of death was presumed to be gastric rupture following impaction with debris, which added to a previous problem of starvation. The problem of plastics arising from greenhouse agriculture should have a relevant section in the conservation plans and should be a recommendation from ACCOBAMS due to these plastics' and sperm whales' high mobility in the Mediterranean Sea. © 2013 Elsevier Ltd.

Borchers D.L.,University of St. Andrews | Zucchini W.,University of Gottingen | Heide-Jorgensen M.P.,Greenland Institute of Natural Resources | Canadas A.,Alnilam Research and Conservation | Langrock R.,University of St. Andrews
Biometrics | Year: 2013

We develop estimators for line transect surveys of animals that are stochastically unavailable for detection while within detection range. The detection process is formulated as a hidden Markov model with a binary state-dependent observation model that depends on both perpendicular and forward distances. This provides a parametric method of dealing with availability bias when estimates of availability process parameters are available even if series of availability events themselves are not. We apply the estimators to an aerial and a shipboard survey of whales, and investigate their properties by simulation. They are shown to be more general and more flexible than existing estimators based on parametric models of the availability process. We also find that methods using availability correction factors can be very biased when surveys are not close to being instantaneous, as can estimators that assume temporal independence in availability when there is temporal dependence. © 2013, The International Biometric Society.

Canadas A.,ALNILAM Research and Conservation | Vazquez J.A.,ALNILAM Research and Conservation
Biological Conservation | Year: 2014

Links between atypical mass strandings of beaked whales and military manoeuvres have been demonstrated in several parts of the Mediterranean, including the Alboran Sea. Herein, information on the distribution and abundance of Cuvier's beaked whales is presented for the Alboran Sea. Such information is of great importance to allow the impacts of mass strandings, entanglements, etc. to be put in a population context and to highlight the most important areas for this species which may be focus for conservation action. Data used for these analyses come from two sources: summers 2008-2009 on board the vessel Alliance; and 1992-2009 surveys under the umbrella of the NGO Alnitak. A detection function was obtained using distance sampling methods and density surface modeling was undertaken. Availability bias correction factors were estimated for different platforms and vessel speeds and applied during the spatial modeling exercise. The final estimate of density (in animals/km2) corrected for the availability bias was 0.0054 (CV=22%). Based on these results, and a comparison with estimates from elsewhere, it is clear that the Alboran Sea supports one of the highest densities of Cuvier's beaked whales in the world. This information and the proposed management measures are being used by the Spanish Ministry for Agriculture, Food and Environment to assess the possibility of increasing the level of protection of this species by either to promote a proposal for a Marine Protected Area designation or to include Cuvier's beaked whales in the Spanish catalogue of threatened species in the "Vulnerable" category. © 2014 Elsevier Ltd.

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