Geographical species distribution in the Barents Sea under climate change - results from the BarEcoRe project

This report presents a study of possible changes in species’ spatial distribution in the Barents Sea as a result of possible future changes in the ocean climate. Species Distribution Models (SDMs) are constructed to describe and quantify the relationship between past distribution of species and environmental conditions. On the basis of simple environmental scenarios, the same models are used to project possible changes in individual species’ spatial distributions. The work was conducted under the NFR funded project BarEcoRe: Barents Sea Ecosystem Resilience under global environmental change

The Nature Index: A General Framework for Synthesizing Knowledge on the State of Biodiversity

The magnitude and urgency of the biodiversity crisis is widely recognized within scientific and political organizations. However, a lack of integrated measures for biodiversity has greatly constrained the national and international response to the biodiversity crisis. Thus, integrated biodiversity indexes will greatly facilitate information transfer from science toward other areas of human society. The Nature Index framework samples scientific information on biodiversity from a variety of sources, synthesizes this information, and then transmits it in a simplified form to environmental managers, policymakers, and the public. The Nature Index optimizes information use by incorporating expert judgment, monitoring-based estimates, and model-based estimates. The index relies on a network of scientific experts, each of whom is responsible for one or more biodiversity indicators. The resulting set of indicators is supposed to represent the best available knowledge on the state of biodiversity and ecosystems in any given area. The value of each indicator is scaled relative to a reference state, i.e., a predicted value assessed by each expert for a hypothetical undisturbed or sustainably managed ecosystem. Scaled indicator values can be aggregated or disaggregated over different axes representing spatiotemporal dimensions or thematic groups. A range of scaling models can be applied to allow for different ways of interpreting the reference states, e.g., optimal situations or minimum sustainable levels. Statistical testing for differences in space or time can be implemented using Monte-Carlo simulations. This study presents the Nature Index framework and details its implementation in Norway. The results suggest that the framework is a functional, efficient, and pragmatic approach for gathering and synthesizing scientific knowledge on the state of biodiversity in any marine or terrestrial ecosystem and has general applicability worldwide

Distribution, abondance et stratégie de recherche alimentaire chez les prédateurs supérieurs du Golfe de Gascogne : une étude spatialisée.

Le travail de thèse que nous présentons est avant tout un travail d'interface entre l'écologie marine et les analyses spatialisées. Nous nous intéressons à une communauté d'organismes peu décrite, les prédateurs supérieurs du golfe de Gascogne, alors même que cet écosystème a fait l'objet d'une intense activité de recherche depuis la deuxième moitié du XXème siècle. Jusqu'en 1990, la plupart des travaux concernaient sa structure océanographique et ses communautés planctoniques et benthiques (Pingree 1969, Belderson & Kenyon 1976, Sibuet 1977, Treguer et al. 1979, Cornet et al. 1983 Pingree et al. 1986, Garcia-Soto et al. 1990, New & Pingree 1990, Pingree & Le Cann 1992). L'activité de recherche s'est ensuite diversifiée vers d'autres composantes de l'écosystème et notamment les populations de poissons pélagiques, en particulier à travers le prisme de l'exploitation du golfe par la pêche (Dorel et al. 1991, Koutsikopoulos & Lacroix 1992, Blanchard & Boucher 2001, Poulard 2001, Petitgas et al. 2003). L'objectif premier de ce travail de thèse est de poursuivre cet effort et d'étendre les connaissances sur l'écosystème « Golfe de Gascogne » en fournissant à la communauté scientifique une information précise sur la communauté des prédateurs supérieurs, tant sur le plan descriptif que sur le plan fonctionnel. Dans ce but, la prise en compte de la dimension spatiale est indispensable, car elle permet au-delà de l'outil de représentation cartographique de comprendre les interactions que ces organismes entretiennent entre eux et avec leur environnement. Notre travail est inter-disciplinaire et fait appel à la fois aux connaissances accumulées sur la structure et le fonctionnement de l'écosystème du golfe de Gascogne, aux outils d'analyse spatiale développés récemment et aux concepts d'écologie comportementale qui ont émergés ces dernières années. Ce travail utilise les concepts et les méthodes de l'analyse spatiale pour apporter une information écologique aussi bien aux scientifiques qu'aux gestionnaires dans des domaines variés allant de la description de la communauté des prédateurs supérieurs (distribution, abondance, habitat, variabilité), de son intégration en tant qu'élément constitutif du réseau trophique, de son utilité en tant qu'indicateur biologique et enfin de sa contribution à une réflexion générale sur les processus comportementaux impliqués dans la vie et la recherche de nourriture en groupe. Nous nous sommes donc attachés à utiliser les méthodes spatiales pour répondre à des questions écologiques posées par la communauté de prédateurs supérieurs. Nous espérons que notre travail servira de point de repère dans le futur pour les prochaines études concernant les prédateurs supérieurs du golfe de Gascogne

The ROMER data (RData)

The 2001-2002 data analysed in this paper. List of variables: MonthfromOctober: ID of month from October 2001, e.g. 2 stands for November 2001; Alcides: Number of auks counted within 5km segments from the side without glare; SeaState: Sea state at Beaufort scale; CloudCover: Cloud cover from 0 to 4; DistCoast: Distance from the coast in kilometers

Distribution, abondance et stratégies de recherche alimentaires chez les prédateurs supérieurs du golfe de Gascogne (une approche spatialisée)

Cette étude propose de jeter un regard neuf sur une communauté d animaux mal connue et étudiée, la communauté des prédateurs supérieurs (oiseaux/mammifères marins) du golfe de Gascogne. Sur la base de transects réalisés à la fois en avion et en bateau, et en nous appuyant sur les outils de l analyse spatialisée, nous caractérisons pour la première fois la distribution et l abondance de ces prédateurs sur le plateau continental atlantique français, offrant ainsi des outils supplémentaires de gestion dans le contexte de la mise en place des aires marines protégées. Après une étude approfondie des biais associés aux échantillonnages aérien en mer, notre travail s articule autours de trois axes principaux : distribution spatiale et variabilité temporelle, abondance et consommation de nourriture, enfin stratégies de recherche alimentaires. Du point de vue fondamental, nous proposons une approche novatrice pour mesurer la variabilité temporelle de la distribution spatiale des animaux. Cette approche nous a permis de mettre en évidence les zones les plus stables et les plus variables de la distribution des oiseaux marins du golfe de Gascogne, ainsi que les échelles spatiales auxquelles s exprime cette variabilité. Nous avons également modélisé les habitats à large échelle des mammifères marins, mettant en évidence les zones les plus importantes pour leur distribution. Nos estimations d abondance, couplées aux travaux plus anciens sur le régime alimentaire des prédateurs nous a également permis d estimer que leurs consommations en proies était du même ordre de grandeur, en biomasse, que les volumes prélevés par l activité de pêche. Enfin, en nous appuyant sur le modèle d étude fou de bassan , nous mettons en évidence une organisation spatiale à fine échelle en réseau qui permet aux oiseaux de collecter efficacement l information publique provenant de leurs congénères, augmentant ainsi leur chance de trouver de la nourriture au sein d un milieu marin hautement variable, dynamique et imprévisible. Ces résultats montrent l importance de l utilisation des outils et des concepts de l écologie spatiale pour répondre à des questions à la fois fondamentale et appliquées sur la structure, le fonctionnement et la gestion des populations.LA ROCHELLE-BU (173002101) / SudocSudocFranceF

Distribution maps and minimum abundance estimates for wintering auks in the Bay of Biscay, based on aerial surveys

The “Erika” oil spill has killed more seabirds than any before in Europe: nearly 70 000 guillemots (Uria aalge) were found dead or alive on beaches, and many more are thought to have been killed. This unexpectedly high number highlighted how poor our knowledge was on spatial and temporal patterns in seabird distribution in the Bay of Biscay. The purpose of our research project, “ERIKA-Avion”, was to fill this gap, providing the first distribution maps and abundance estimates of seabirds wintering in the entire shelf of the Bay of Biscay. In particular, we analysed fine-grained distribution maps for the wintering auks, comparing their areas of highest density with the oil drift area, and proposing for the first time (although preliminarily) minimal abundance estimates for these birds in this area

Characterising the temporal variability of the spatial distribution of animals: an application to seabirds at sea

International audienceUnderstanding the patterns of spatial and temporal variations in animal abundance is a fundamental question in ecology. Here, we propose a method to quantify temporal variations in animal spatial patterns and to determine the spatial scale at which such temporal variability is expressed. The methodology extends from the approach proposed by Taylor (Taylor, L. R. 1961. Aggregation, variance and the mean. Nature 189: 732735) and relies on models of the relationship between temporal mean and variance in animal abundance. Repeated observations of the spatial distribution of populations are used to construct spatially explicit models of Taylor's power law. The resulting slope parameters of the Taylor power law provide local measures of the temporal variability in animal abundance. We investigate if the value of the slope varies significantly with spatial location and with spatial scale. The method is applied to seabirds distribution in the Bay of Biscay. We study four taxa (northern gannets, large gulls, auks and kittiwakes) that display distinct geographical distribution, spatial structure and foraging strategy. Our results show that the temporal variability associated to the spatial distribution of northern gannets is high and spatially homogeneous. By contrast, kittiwakes present large geographical areas associated with high and low variability. The temporal variability of auk's spatial distribution is strongly scale-dependent: at fine scale high variability is associated to high abundance, but at large scale high variability is associated to the external border of their distribution range. The method provides satisfactory results and useful information on species spatio-temporal distribution

Data from: Spatio-temporal modelling of auk abundance after the Erika oil spill and implications for conservation

Species distribution models are widely used in applied ecology and conservation. While accounting for spatial dependences is now the rule, temporal dependences have rarely been dealt with explicitly. In this study, we analyse wintering auk distribution in the Bay of Biscay and English Channel and estimate changes in abundance within and between years while accounting for space–time dependencies. We then propose a retrospective estimate of the impact of the Erika oil spill that occurred in December 1999. Two series of extensive aerial surveys, repeated at intervals of 1–2 months, were carried out at a 10-year interval off the French Atlantic coast (2001–2002 and 2011–2012). Spatially and temporally explicit Bayesian models were fitted to these data to provide spatio-temporal predictions of auk abundance. These were then used to compare abundances within the area affected by the Erika oil spill two and twelve years after the catastrophe. The results showed that 1·55 million auks wintered in the study area in 2011–2012. The main wintering area was the English Channel (more than one million auks) but the Bay of Biscay also became an important area in the middle of winter (470 000 auks) owing to a strong southward shift in auk distribution. Two years after the catastrophe (2001–2002), the area affected by the Erika oil spill hosted a small proportion of auks of the Bay of Biscay – about 80 000 individuals. This number increased by more than three times 10 years later and reached 270 000 individuals, whereas no significant change was detected elsewhere. We suggest that it could result from a recovery after the extra-mortality induced by the Erika oil spill. Policy implications. This study identified major auk wintering areas, with abundances much higher than previously realized. Oil spills have occurred regularly in these areas, with major delayed impacts on auk breeding populations. The worst case scenario would be if a major oil spill occurred in the English Channel in February, when abundance reaches one million auks. Although such a disaster has not so far occurred, stricter policies on the transport of hydrocarbons should be implemented to prevent such a possibility

Utvikling av metodikk for arealrepresentativ overvåking av utvalgte invertebratgrupper. Pilotprosjekt Naturindeks for Norge

Öberg, S., Gjershaug, J. O., Certain, G. & Ødegaard, F. 2010. Utvikling av metodikk for areal-representativ overvåking av utvalgte invertebratgrupper. Pilotprosjekt Naturindeks for Norge. – NINA Rapport 555. 50 s. Naturindeks for Norge skal bidra til å måle om Norge når sine internasjonale forpliktelser om å stanse tapet av biologisk mangfold. For at en naturindeks skal avspeile det biologiske mangfoldet er det nødvendig å inkludere data på terrestriske invertebrater. Hensikten med dette prosjektet var å utvikle metodikk for arealrepresentativ overvåking av utvalgte terrestriske invertebratgrupper gjennom et pilotprosjekt med tanke på levering av data til Naturindeks. Det har blitt tatt utgangspunkt i grupper som er enkle å registrere, er sårbare for miljøendringer og representerer ulike økologiske funksjoner. Dagaktive sommerfugler og humler er viktige grupper i denne sammenheng både som planteetere og pollinatorer, mens edderkopper er representanter for predatorene. Pilotprosjektet er begrenset til fylkene Østfold og Vestfold, og til naturtyper som faller innenfor åpen mark i lavlandet. Til sammen er 18 Lucas-flater (landsdekkende rutenettverk med 18 km avstand mellom rutene) blitt undersøkt for disse utvalgte gruppene, 6 flater i Vestfold og 12 flater i Østfold. Hver flate er 1,5*1,5 km. Ved hvert hjørne ble fem transekter á 50 m lagt ut. Naturtypene ved transektene kan deles inn i åpen gressmark, åpen skogsmark og våtmark. Gjennom inventeringene ble sommerfugler og humler bestemt til art. Blomsterdekke ble også registrert hver gang i hvert transekt. Inventeringene ble gjentatt tre ganger i løpet av sommeren for å fange opp forskjellige arters fenologi, nemlig andre halvdel av mai, juni og juli. Fallfeller ble benyttet til å fange edder-kopper på fire flater. Med tanke på det totale artssamfunn som finnes i Østfold og Vestfold ble det registrert et rela-tivt stort antall av de arter som er mulig å påvise gjennom det nettverk og den tilfeldige innsam-lingsmetode som ble brukt i prosjektet. I Østfold og Vestfold er det totale artstilfanget litt mer enn 70 dagaktive sommerfuglarter og 20 humlearter, hvorav 47 arter sommerfugler og 14 arter humler ble registrert i dette studiet. Overvåking av vanlige arter er viktig blant annet for tidlig å kunne detektere populasjonsned-ganger. Ordinasjonsanalysene indikerer at vi i hovedsak har registrert vanlige, habitatgenerelle arter der naturtypene i liten grad forklarer hvor artene ble funnet. Noen få sommerfuglarter ble nesten utelukkende funnet i åpen skogsmark og våtmark, men ellers synes det som at alle stu-derte grupper ble registrert i større antall i åpen gressmark. Når det gjelder fylkene ble det re-gistrert flere individer av sommerfugler og humler, og for sommerfugler også flere arter, i Øst-fold enn i Vestfold. Dette kan delvis forklares av at en større andel av transektene i Østfold var beliggende i åpen gressmark enn i Vestfold, men også fordi fylkene har forskjellig artstilfang. Av de tre periodene var slutten av juni og slutten av juli de individrikeste for både sommerfugler og humler. For sommerfugler er det tydelig at flere arter er knyttet til de to siste periodene samt at det er stor utskiftning av arter mellom periodene. Hos humler er det kjønn (kaste), og ikke ulik fenologi hos forskjellige arter (som hos sommerfugler) som forklarer toppene i individantall, da humlearbeidere ble funnet i høyere grad i slutten av juni og juli. Det ble funnet en positiv sammenheng mellom antall individer av sommerfugler og humler og blomsterdekke. Det at mange sommerfugler og humler synes å foretrekke åpen gressmark framfor åpen skogsmark og våtmark kan forklares med at blomsterdekket var høyere i åpen gressmark. Vi har benyttet metodikk som kan videreutvikles, blant annet med tanke på utvalg av naturty-per, design og inventering. På bakgrunn av erfaringer fra pilotstudiet vurderer vi å ikke inklude-re edderkopper i en fremtidlig overvåking av invertebrater til Naturindeks pga stort ressursbe-hov knyttet til artsbestemmelse. Til tross at forklaringsgradene i de multivariate analysene med naturtyper var lave, er det for sommerfugler likevel grunn til å fortsette å klassifisere de åpne naturtypene ved transektene til åpen gressmark, åpen skogsmark og våtmark. Det kan imidler4 tid vurderes i hvilken grad man skal inkludere indeks for humler i åpen skogsmark og våtmark. Ellers er registreringsopplegget i pilotprosjektets vurdert som formålstjenlig. Ulike arter vil respondere forskjellig på ulike påvirkninger og endringer i landskapet. Artssam-mensetningen av invertebrater reflekterer således arealenes tilstand. Vi har derfor laget ”for-ventningssamfunn” for hvilke arter av sommerfugler og humler man forventer å finne i fylkene og i de undersøkte naturtypene. Hvordan disse forventningssamfunn kan brukes som referan-severdier for sommerfugler og humler som indikatorer i Naturindeks trenger fremdeles å testes og utvikles. Erfaringene med pilotprosjektet har alt i alt vært positive med tanke på mulighetene for å bruke sommerfugler og humler som tilstandsindikatorer i Naturindeks. Tanken er at prosjektet kan utvides til nasjonal skala med påbygging av moduler for andre naturtyper. En slik utvidelse vil innebære opplegg for betydelig involvering av frivillige, og en eventuell fortsettelse innebærer at det må utvikles et system for organisering og opplæring av frivillige.Öberg, S., Gjershaug, J. O., Certain, G. & Ødegaard, F. 2010. Development of methodology for area representative monitoring of chosen invertebrate groups. Pilot project Nature Index for Norway. – NINA Report 555. 50 pp. The Nature Index for Norway is intended as a tool to measure progress towards halting the loss of biodiversity as stated in international agreements. For such an index to mirror the over-all biodiversity it is necessary to include data on terrestrial invertebrates. The purpose of the current pilot project was to develop methodology for area representative monitoring of chosen terrestrial invertebrate groups with the intention of delivering data to the Norwegian Nature In-dex. Groups which are easy to register, are vulnerable to environmental changes, and represents different ecological functions have been chosen. Day-active butterflies and bumble-bees are important groups in this context, both as herbivores and pollinators, whereas spiders are representatives of the predators. The pilot project has been restricted to the regions Østfold and Vestfold in southern Norway, and to nature types within open lowland. The chosen groups have been registered in a total of 18 sites from the Lucas-grid (country covering grid network with 18 km distance between grids), 6 sites in Vestfold and 12 sites in Østfold. Every site is 1.5*1.5 km. Five transects á 50 m were laid out at each corner. The na-ture types at the transect locations can be divided into open grassland, open woodland, and wetland. Butterflies and bumblebees were determined to species and cover of flowering plants was registered during the inventories. The inventories were repeated three times during the summer in order to include the phenology of different species, more specifically in the last half part of May, June, and July. Pitfall traps were used to catch spiders at four sites. Considering the total species pool in Østfold and Vestfold, we registered a substantial number of the species that are possible to find with the network and random sampling method used in the project. The species pool in Østfold and Vestfold consist of around 70 and 20 species of day active butterflies and bumblebees respectively, and we found 47 and 14 species of butter-flies and bumblebees respectively. Common species are important to monitor for instance in order to detect early declines in populations. The ordinations indicate that we mainly caught common and habitat general spe-cies, where the nature types merely explained to a small part where the species were found. Still, some of the butterfly species were found almost exclusively in open woodland and wet-land. Besides these species, all the studied groups were found mainly in open grassland. When considering the regions, a higher number of individuals of butterflies and bumblebees, and for butterflies also a higher number of species, were found in Østfold compared to Vest-fold. The reason for this can in part be that a larger portion of transects in Østfold was situated in open grassland compared to Vestfold, but also because the regions have different species pools. When taking the different periods studied into account, the highest numbers of individu-als was found in the last half part of June and the last half part of July. The number of butterfly species was higher in the last periods as well and there was also a big shift in species among the three periods. For bumblebees it is the different sexes rather than the phenology in differ-ent species (as for butterflies) that explains the increase in individual numbers, as bumblebee workers were found to a larger extent in the last half part of June and July. The butterflies’ and bumblebees’ attraction to open grassland can be explained by the higher coverage of flowering plants compared to open woodland and wetland, as we found a positive correlation between the number of individuals of butterflies and bumblebees and cover of flowering plants. We have employed methodology that can be developed further, for example choice of nature types, design, and inventory methods. As a result of experience we are considering to leave out spiders in a future monitoring of invertebrates in the Nature Index due to large resource use. Despite the fact that the levels of explanation in the multivariate analyses were low, it is still motivated to define the nature types to open grassland, open woodland, and wetland con-sidering butterflies, but it should be evaluated to what extent an index for bumblebees in open woodland and wetland should be included. Otherwise, most part of the design and inventory methods have been assessed as suitable. Different species will respond in various ways to pressures and changes in the landscape. As a consequence, the species composition will reflect the condition of the areas. Therefore, we have made lists of “expected communities of species”, which contains species of butterflies and bumblebees that can be found in the regions and in the investigated nature types. In what way these communities will be used as reference values in a calculation of indicators based on butterflies and bumblebees in the Nature Index needs further testing and development. The experiences from the project have in total been encouraging with regard to the possibilities of using butterflies and bumblebees as indicators in the Nature Index. The plan further on may be to expand the project to a larger scale in the country, thus adding on regions and other na-ture types. Such an extension will imply to plan for considerable participation of volunteers, and a potential continuation ought to consist of development of organization and education of volunteers

Small pelagic fish data (Appendix S6)

The data used in Appendix S6 (from ICES)