Seabird Ecology Lab
Movement ecology, conservation biology, symbiotic interactions and marine environmental chemistry in seabirds
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How do Audouin’s gulls interact with fishing vessels? The GAUDIN project informs on the effects of fisheries and the role of RAMPE in the conservation of this species
Associação Projecto Vitó, in collaboration with University of Barcelona and with the logistic support of MiraNatura are announcing the launching of the streaming on YouTube of the first LiveCam ever set inside a Gongon petrel’s nest (Pterodroma feae), located at the Fogo Natural Park, in Cape Verde.
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How do Audouin's gulls interact with fishing vessels? The GAUDIN project informs on the effects of fisheries and the role of RAMPE in the conservation of this species
June 10, 2021
The RAMPE
RAMPE is the Spanish acronym of the Red de Áreas Marinas Protegidas de España (Spanish network of marine protected areas; Ley 41/2010, del 29 de diciembre, de protección del medio marino). The RAMPE contains the marine protected areas in Spain and its main objective is to ensure the protection, conservation and recovery of the Spanish natural heritage and marine biodiversity. The areas in the RAMPE are subject to different categories of protection: marine protected areas, special areas of conservation, special protection areas for birds, sites of community importance and marine reserves, among others (Figure 1).
Figure 1. Areas included in the RAMPE. Different colours show different categories of protected areas. AMP: marine protected areas, Reserva Marina: marine reserves, ZEC: special areas of conservation, ZEPA: special protection areas for birds, LIC: sites of community importance.
What is the main objective of the GAUDIN project?
“GAUDIN: Audouin’s gull as a tool to improve the management of the in the Spain’s east coast” is a project developed by our team, the Seabird Ecology Lab, from the Biology Faculty and the Institute for Research on Biodiversity (IRBio) from the University of Barcelona, with the collaboration of Asociación de Naturalistas del Sureste (ANSE) and the Spanish Institute of Oceanography (IEO).
During this project, we have investigated the role of RAMPE in the conservation of the Audoun’s gull (Ichtyaetus audouinii; Figure 2) in the Spain’s east coast, considering how, where and when they interact with fishing vessels. Moreover, we have taken into account the age class of the gulls (adults and juveniles) in the study of the use of RAMPE and in the interactions with fishing vessels.
GAUDIN, in the framework of the 2019 call of the “ayudas por la Fundación Biodiversidad F.S.P, en régimen de concurrencia competitiva, para la conservación de la biodiversidad marina en España”, has the support of Fundación Biodiversidad from the Ministry for the Ecological Transition and the Demographic Challenge.
Figure 2. Adult Adouin’s gull. Credit: Raül Ramos.
How do we study the movement of Audouin's gulls? And their interactions with fisheries?
To address the movement of Audouin’s gulls and their interactions with fishing vessels, we used tracking data from both the gulls and the vessels. On one hand, we used remote tracking devices (GPS/GSM), which are extremely useful to study the movements and distribution of seabirds (among other animals), because they register the animal’s location every few minutes, allowing us to study how they use the RAMPE and how they interact with fishing vessels. For this purpose, we monitored 15 Audouin’s gulls in 2020, both adults and juveniles (Figures 3 and 4), especially during spring and summer, when they incubate their eggs, rear their chicks and start their migration. The studied gulls were captured and equipped with GPS/GSM devices in the Parque Regional Salinas y Arenales de San Pedro del Pinatar (Figure 5), a protected natural space of the Region of Murcia.
Figure 3. GPS/GSM device placed on an adult Audouin’s gull. Credit: Raquel Castillo.
Figure 4. GPS/GSM device placed on a juvenile Audouin’s gull. Credit: Ángel Sallent.
Figure 5. Audouin’s gulls breeding colony in the Parque Regional Salinas y Arenales de San Pedro del Pinatar, Region of Murcia. Credit: Raquel Castillo.
On the other hand, a novel algorithm allowed us to detect situations in which a bird is interacting with a vessel (bird and vessel are separated by maximum 1.5 km, and the interaction lasts longer than 10 min while the bird is flying at a low speed, indicating that it is probably feeding). This algorithm, developed in the framework of another project that we carried out in 2020-2021 (AMARYPESCA, supported by Fundación Biodiversidad and with EMFF funds), uses 1) tracking data from the vessel monitoring system (VMS), as well as tracking data from GPS devices carried by fishing vessels from collaborator fishermen, and 2) tracking data from Audouin's gulls equipped with GPS/GSM devices.
Results and management suggestions for the RAMPE and fishing activities
Results indicate that a 30% of the at sea-positions of adult Audouin's gulls and a 34% of the at sea-positions of juvenile gulls took place inside one of the RAMPE spaces (Figure 6). In general, the marine areas most used by both the adult and juvenile gulls (Figures 7 and 8) are near the coastline and are partially protected by the RAMPE, which is relevant for the conservation of the species.
Figure 6. Locations registered by the GPS/GSM devices carried by Audouin’s gulls (adults in black, juveniles in blue) in the Spain's east and south coasts. White polygons show the RAMPE.
Figure 7. Distribution of adult Audouin’s gulls. Warmer colours indicate higher concentration of GPS/GSM locations. White polygons show the RAMPE.
Figure 8. Distribution of juvenile Audouin’s gulls. Warmer colours indicate higher concentration of GPS/GSM locations. White polygons show the RAMPE.
Regarding the interactions with fishing vessels, the vast majority of interactions (92%) between Audouin’s gulls and the vessels (VMS data) occurred with the purse-seine fleet (during the night) and the trawl fleet (during the day), and in working days. With respect to age, the amount of interactions with both fleets were similar for adult gulls, but juvenile gulls interacted more frequently with trawlers (Figure 9 and 10). The purse-seine and trawl fleets are the most covered by the VMS, operate mainly in working days, and both offer food resources for seabirds. On the contrary, interactions with the pelagic longline and artisanal fleets were the least frequent for both age classes.
In general, the interactions between Audouin’s gulls and fishing vessels occurred outside the RAMPE. Only a fifth of the interactions detected for adult gulls (21%) and a third of the interactions detected for juvenile gulls (32%) took place inside the RAMPE.
Figure 9. Interactions detected between adult Audouin’s gulls and all flets (top map), the purse-seine fleet (middle map) and the trawl fleet (bottom map) (VMS data). Circle size indicates the interaction duration. Gull’s distribution is also shown; warmer colours indicate a higher concentration of locations. White polygons show the RAMPE.
Figure 10. Interactions detected between juvenile Audouin’s gulls and all flets (top map), the purse-seine fleet (middle map) and the trawl fleet (bottom map) (VMS data). Circle size indicates the interaction duration. Gull’s distribution is also shown; warmer colours indicate a higher concentration of locations. White polygons show the RAMPE.
Since the RAMPE covers an important part of the coastal waters used by Audouin’s gulls in the southern half of Spain, and most of the gull foraging trips – when feeding at sea – were close to the coastline, the RAMPE can be a good tool to protect the areas most used by the studied gulls, and therefore an useful tool for their conservation. However, most RAMPE areas lack management measures aimed at protecting seabirds in the marine environment or at reducing the human activities developed there (fishing, aquaculture, maritime traffic, tourism or leisure activities; with the exception of marine reserves). In light of these results, there is a need to design and implement management plans to regulate certain human activities in the RAMPE spaces most used by these gulls, at least during their breeding period and the beginning of their migration. It is also needed to implement mitigation measures to reduce seabird bycatch in fishing vessels that operate in coastal areas, both inside and outside the RAMPE, mainly in the Spain’s east coast.
Despite Audouin’s gull has recovered from population declines over the last decades, it still has a limited distribution and most individuals breed in Spain, so there is a need to continue monitoring the populations, evaluating the risks, and designing appropriate conservation measures.
Figure 11. Gulls (different species) attending a fishing vessel. Credit: Salvador García Barcelona.
Maps developed by Raquel Castillo.
How do seabirds interact with fisheries and aquaculture? AMARYPESCA project offers new insights on the effects of these activities and the role of RAMPE in the conservation of seabirds
March 10, 2021
What does RAMPE mean?
RAME is the Spanish acronym of the Red de Áreas Marinas Protegidas de España (Spanish network of marine protected areas; Ley 41/2010, del 29 de diciembre, de protección del medio marino). The RAMPE contains the marine protected areas in Spain and its main objective is to ensure the protection, conservation and recovery of the Spanish natural heritage and marine biodiversity. The areas in the RAMPE are subject to different categories of protection: marine protected areas, special areas of conservation, special protection areas for birds, sites of community importance and marine reserves, among others (Figure 1). However, many of these categories do not have a specific management plan that considers the interactions of seabirds with fisheries and aquaculture.
Figure 1. Areas included in the RAMPE. Different colours show different categories of protected areas. AMP: marine protected areas, Reserva Marina: marine reserves, ZEC: special areas of conservation, ZEPA: special protection areas for birds, LIC: sites of community importance.
What is the main objective of the AMARYPESCA project?
“AMARYPESCA: Seabirds as a tool to improve the management of fisheries and aquaculture in the context of a sustainable RAMPE” is a project developed by our team, the Seabird Ecology Lab, from the Biology Faculty and the Institute for Research on Biodiversity (IRBio) from the University of Barcelona, together with the Asociación de Naturalistas del Sureste (ANSE), also with the collaboration of the Spanish Institute of Oceanography (IEO).
During this project, we have investigated the role of the RAMPE in the conservation of seabirds in the Spain’s east coast and the Canary Islands, considering how, where and when they interact with fishing vessels and fish farms.
AMARYPESCA, in the framework of the 2019 call of the Pleamar Program, has the support of Fundación Biodiversidad from the Ministry for the Ecological Transition and the Demographic Challenge, and is co-financed by the European Maritime and Fisheries Fund (EMFF).
How do we study the movement of seabirds? And their interactions with fisheries and aquaculture?
To address the movement of seabirds and their interactions with fishing vessels and fish farms, we have tracked several populations from different species (you can see which ones in the publication entitled “Marine protected areas and the conservation of seabirds. Data collection”, in this webpage) and used different methodologies.
On one hand, remote tracking devices are extremely useful to study the movements and distribution of seabirds (among other animals), because they register the animal’s location every few minutes, allowing us to study how they use the RAMPE and the fish farms, and how they interact with fishing vessels. For this purpose, we made a big effort of seabird monitoring in 2020, especially during spring and summer, when several species incubate their eggs and rear their chicks. Moreover, with the collaboration of other research groups and through other projects, we have gathered tracking data of other seabird populations dating back to 2011, to broaden the scope of the analyses performed in this project.
On the other hand, the development of a novel algorithm that uses 1) tracking data from the vessel monitoring system (VMS), as well as tracking data from GPS devices carried by fishing vessels from collaborator fishermen, and 2) tracking data from seabirds equipped with GPS devices, allowed us to detect situations in which a bird is interacting with a vessel (bird and vessel are separated by maximum 1.5 km, the interaction lasts longer than 10 min while the bird is flying at a low speed, indicating that it is probably feeding). With this newly developed methodology, we have obtained detailed information regarding when, where and for how long do seabirds interact with fishing vessels.
With regards to aquaculture, we obtained the location and size of the fish farms in Spain’s east coast, to determine when a seabird equipped with a GPS tracking device goes there. We also conducted surveys to the fish farm workers to identify which seabird species (other than those equipped with GPS devices) are attending the farms.
Results and management suggestions for the RAMPE and human activities at sea
After a profound analysis of the overlap between the RAMPE and the distribution of seabirds along ten years, we see that most areas that seabirds use for foraging are located within the RAMPE, at least partially (Figure 2 shows an example with one of the studied species, the Scopoli's shearwater). However, in other cases the foraging areas were much larger than the areas protected by the RAMPE (Figures 3 and 4, showing the distribution of the Bulwer’s petrel and the Cory’s shearwater) and we also identified two non-protected areas that are very important for some of the seabird populations studied: Golfo de Mazarrón (Figure 5, showing the distribution of the European storm petrel) and the coasts of the Barcelona province (Figure 6, with the distribution of the Balearic shearwater).
Figure 2. Distribution of the Scopoli’s shearwater population (data holder: Seabird Ecology Lab) breeding in Menorca (orange circle). Colour shows the percentage of monitored individuals using each area, from a single individual (dark blue) to all of them (yellow). Coral lines show the RAMPE. See the high percentage of individuals that use Canal de Menorca, a protected area.
Figure 3. Distribution of the Bulwer’s petrel population (data holder: Seabird Ecology Lab) breeding in Montaña Clara islet (orange circle). Colour shows the percentage of monitored individuals using each area, from a single individual (dark blue) to all of them (yellow). While RAMPE (coral lines) mainly covers coastal areas, Bulwer’s petrels make long foraging trips to pelagic zones (not protected).
Figure 4. Distribution of the Cory’s shearwater population (data holder: Seabird Ecology Lab) breeding in Gran Canaria (orange circle). Colour shows the percentage of monitored individuals using each area, from a single individual (dark blue) to all of them (yellow). While RAMPE (coral lines) mainly covers coastal areas, Cory’s shearwaters make long foraging trips to the coasts of Morocco and Western Sahara (not protected).
Figure 5. Distribution of the European storm petrel population (data holder: Seabird Ecology Lab) breeding in Palomas island (orange circle). Colour shows the percentage of monitored individuals using each area, from a single individual (dark blue) to all of them (yellow). See the high percentage of individuals that use Golfo de Mazarrón, an area not protected by the RAMPE (coral lines).
Figure 6. Distribution of the Balearic shearwater population (data holder: Tim Guilford's Lab) breeding in Mallorca (orange circle). Colour shows the percentage of monitored individuals using each area, from a single individual (dark blue) to all of them (yellow). See the high percentage of individuals that use the coasts of the Barcelona province, another area currently not protected by the RAMPE (coral lines).
Regarding the interactions between seabirds and fisheries, we detected interactions mainly with the trawl and purse-seine fleets, which are the most abundant and provide food for seabirds through fishery discards at predictable times every day. For Scopoli’s and Cory’s shearwaters, as well as for European shags, most of the interactions with fishing vessels occur within the RAMPE, particularly with trawlers, purse seiners and artisanal vessels, which operate along the coastline (see Figure 7 for an example of interactions between Scopoli’s shearwaters and different fishing fleets). In other cases, such as the Balearic shearwater (critically endangered according to UICN), only a small proportion of the interactions with fishing vessels occur within the RAMPE (Figure 8).
Regarding the interactions between seabirds and fish farms, the data obtained from seabirds equipped with GPS tracking devices, together with the surveys conducted with fish farm workers, indicate that two species are regularly present in these farms: yellow-legged gulls and European shags.
Figure 7. Seabird – fishing vessel interactions detected between Scopoli's shearwaters and the trawl (top left), purse seine (top right) and pelagic longline (bottom) fleets in Spain’s east coast and the Balearic Islands (data holder: Seabird Ecology Lab for the Scopoli’s shearwater data, Secretaría General de Pesca and IEO for the VMS data). Circle size indicates the interaction duration. Green lines show the RAMPE. See that most interactions with trawlers and purse seiners occur inside the RAMPE, while many interactions with pelagic longliners happen outside of it. Arrastre: trawl, cerco: purse-seine, palagre de superficie: pelagic longline.
Figure 8. Seabird – fishing vessel interactions detected between Balearic shearwaters and the trawl, purse-seine, pelagic longline and artisanal fleets (data holder: Tim Guilford's Lab for the Balearic shearwater data, Secretaría General de Pesca and IEO for the VMS data). Circle colour indicates the fishing fleet, and circle size indicates the interaction duration. Green lines show the RAMPE. See that most interactions occur outside the RAMPE. Arrastre: trawl, artesanales: artisanal fleet, cerco: purse-seine, palagre de superficie: pelagic longline.
Considering all these previous findings, we show that the RAMPE covers the waters surrounding most breeding colonies of the studied seabird populations, which could be particularly relevant for species that make short foraging trips during the breeding period, such as the Audouin’s gull, yellow-legged gull and European shag. However, most RAMPE areas lack management measures aimed at protecting seabirds in the marine environment, and therefore there is a need to design and implement management plans that regulate human activities carried out in these areas. Such measures could include recreational fishing restrictions, the requirement to install mitigation measures to reduce bycatch of seabirds (tori lines and night setting, among others, see Cortés and González‐Solís 2018), and even the temporary closure of certain fishing areas during the breeding period of some seabird species. Management measures like these could have a positive effect on the conservation of Spanish seabird populations, especially those that interact with fishing vessels and fish farms mainly inside the RAMPE.
In the case of those seabirds that make long foraging trips and show large distributions in pelagic zones, such as the Bulwer’s petrels (Figure 4) and the Cory’s shearwaters (Figure 5) studied here, the proportion of RAMPE overlapping with their distribution is very small (the RAMPE mainly covers coastal areas). In such cases, fisheries management and mitigation measures to reduce seabird bycatch risks could be much more efficient than the establishment of new coastal protected areas.
With regards to the interactions specifically between coastal seabirds and fish farms, mitigation measures that reduce the attendance to the farms should be considered, otherwise these interactions could create a non-desired dependency on food available for seabirds in fish farms. Moreover, in the case of overabundant birds like the yellow-legged gull, the use of fish farms as a food source could contribute to increase their population numbers, abundant since the 80’s and that competes with other seabirds of smaller size.
Last but not least, given that we identified two areas highly used by seabirds and with a high risk of interaction with fisheries, but not protected, there is a need for the identification of new important areas for the conservation of seabirds in Spain, based on tracking data such as those gathered through this project.
All maps were developed by Virginia Morera.
Use of marine protected areas by Audouin’s gulls during their breeding period and migration
November 20, 2020
The Seabird Ecology Lab (Faculty of Biology from Universitat de Barcelona and the Institute for Research on Biodiversity-IRBio) is developing the project “GAUDIN: La gaviota de Audouin como instrumento para la mejora de la gestión de la RAMPE en el Levante español” (Audouin’s gull as a tool to improve the management of RAMPE in the Spanish east coast). This project has the support of Fundación Biodiversidad from the Ministry for the Ecological Transition and the Demographic challenge, with the collaboration of the Asociación de Naturalistas del Sureste (ANSE) and the Spanish Institute of Oceanography (IEO).
The main objectives of GAUDIN project are 1) to address the role of the Spanish network of marine protected areas (Spanish acronym: RAMPE) in the conservation of an endangered and endemic species to the Mediterranean Sea, the Audouin’s gull (Ichtyaetus audouinii), and 2) to investigate the interactions between Audouin’s gulls and fishing vessels, in order to improve the management of RAMPE and fisheries. These objectives align with LIFE INTEMARES actions, which aim for an efficient management of marine areas from Natura 2000 with the collaboration of the sectors involved and research as main tools for decision making.
To achieve these objectives, we equipped 18 Audouin’s gulls with GPS/GSM tracking devices (Global Positioning System/Global System for Mobile communications). We placed the devices on both adult individuals (during incubation) and chicks (during chick rearing), between May and July from 2020, in the Regional Park of Salinas y Arenales de San Pedro del Pinatar (Murcia). These devices can register a location every minute and send this information via the mobile communications network, which will allow us to investigate the movements of Audouin’s gulls with a very high temporal and spatial resolution.
Since Audouin’s gull is a migratory species, we have been able to obtain movement data during the breeding period, when they were at their breeding colony in the Spanish east coast, and also during their migration, when in general they left towards African coasts. Currently, there are 10 GPS/GSM tracking devices that continue functioning, six of them placed on adult gulls and four on juveniles. The positions gathered by all of them add up to 1,200,000.
Preliminary results show that, during the breeding period (we considered May and June), most locations registered by the GPS/GSM tracking devices took place ashore (overall: 69.3%; per age class: 69.1% adults, 100% juveniles), while just a third of them (30.7%; per age class: 30.9% adults, 0% juveniles) were at sea. Regarding the overlap between Audouin’s gull movements and the RAMPE, only a third (31.6%) of the total locations at sea -all belonging to adult gulls- took place within RAMPE spaces. Since juveniles were equipped with tracking devices by the end of June and they stayed in the breeding colony until migrating, all their positions were ashore and they did not use the RAMPE. All the locations registered during the breeding period and their overlap with the RAMPE are depicted in the following map.
With regards to their migration, most adult gulls equipped with GPS/GSM tracking devices left the breeding grounds between late June and late July, while juvenile gulls migrated -in general- after their parents, from mid-July to early August. Some gulls (both adults and juveniles) travelled long distances in a relatively short amount of time, while others made a few stops while migrating. Moreover, some of them are still on the move. Audouin’s gulls have travelled between 400 and 3,400 km in 1 to 40 days, except for one adult gull that did not leave the Iberian Peninsula.
During their migration (here we considered July and August), the percentage of locations ashore registered by the tracking devices varied between age classes (overall: 57.3%; per age class: 46.6% adults, 67.1% juveniles), being slightly lower (in adults) or higher (in juveniles) than the percentage of positions at sea (overall: 42.7%; per age class: 53.4% adults, 32.9% juveniles). As for the overlap with the RAMPE, the use of these spaces by Audouin’s gulls was scarce: only 9.7% of at sea locations occurred within these spaces (per age class: 8,7% adults, 11.2% juveniles).
With regards to the wintering areas, four out of six adult gulls migrated towards the Atlantic coast of Morocco, Western Sahara and Mauritania, while the other two stayed in the Alborán Sea. Overall, the most frequent wintering and migration areas were Dahkla (Río de Oro Peninsula, Western Sahara) and Nouadhibou (Cabo Blanco Peninsula, on the border between Western Sahara and Mauritania). As for the two adult gulls that stayed in the Alboran Sea, they are currently in Moroccan coasts (provinces of Driouch and Nador) and Spanish coasts (Almería), and the latter did not migrate. Regarding the juvenile gulls (five of them migrated, four still have functioning tracking devices), in general they migrated further away from the breeding colony than adult gulls, given that they have already reached Western Sahara, Mauritania and Senegal. The wintering and migration areas more used by juveniles were Nouadhibou (Western Sahara/Mauritania), Nuakchot (Mauritania) and Dakar (Peninsula of Cape Verde, Senegal).
Click on the following map to explore all the migratory routes and wintering areas of Audouin's gulls.
Despite we need to perform detailed spatial and temporal analyses, as well as take interactions with fisheries into account, these preliminary results show that RAMPE spaces are more used by adult Audouin’s gulls, especially during the breeding period. The lower use of RAMPE by both age classes during migration is related to the migratory behaviour of the species, given that they travel long distances outside national territory.
Furthermore, the wintering areas and migratory routes used up until this moment by Audouin’s gulls in general agree with areas previously described as important for their migration (https://tinyurl.com/yy5j5ul7). The Canary Current, characterised by cold and rich waters, has a high productivity in the Atlantic coast of northern Africa, which allows Audouin’s gulls to obtain food (mainly epipelagic fishes) both from natural and anthropogenic sources (fishery discards from fishing vessels and in ports). Agreeing with this, there are industrial and artisanal fishing fleets in Dakhla, Nouadhibou and Dakar, which are probably exploited by Audouin’s gulls. Moreover, the single Audouin’s gull that stayed in Spain frequently visits Adra’s port (Almería), other ports in the area and croplands, which suggest that this non-migratory individual also utilises resources derived from human activities.
These preliminary results contribute with relevant data to the knowledge on movements and use of RAMPE by Audouin’s gulls in the Spanish east coast, as well as on their wintering areas and migratory routes in the Atlantic and Mediterranean coasts of northern Africa. These results, together with the analysis of their interactions with fisheries, will help in achieving the objectives of the GAUDIN project for a better management of RAMPE and fishing activities.
Marine protected areas and the conservation of seabirds
Data collection
26th October 2020
We have already carried out the field work and data collection of the project “AMARYPESCA: Las aves marinas como instrumento para la mejora de la gestión pesquera y acuícola en el contexto de una RAMPE sostenible” (seabirds as a tool to improve the management of fisheries and aquaculture in the context of a sustainable RAMPE). This project has two objectives: 1) determining the role of the Spanish network of marine protected areas (Spanish acronym: RAMPE) in the conservation of seabirds, and 2) addressing the interactions between seabirds and both fishing and aquaculture activities, in order to improve the management of RAMPE and of the human activities at sea. These objectives align with LIFE INTEMARES actions, which aim for an efficient management of marine areas from Natura 2000 with the collaboration of the sectors involved and research as main tools for decision making.
AMARYPESCA project is part of the 2019 call of the Pleamar programme, which has the support of Fundación Biodiversidad (biodiversity foundation) from the Ministry for the Ecological Transition and the Demographic challenge and is co-funded by the European Maritime and Fisheries Fund (EMFF). The project is being developed by the Seabird Ecology Lab, from the Faculty of Biology from Universitat de Barcelona and the Institute for Research on Biodiversity (IRBio), and its partner organisation, the Asociación de Naturalistas del Sureste (ANSE), with the collaboration of the Spanish Institute of Oceanography (IEO).
Most of the fieldwork of AMARYPESCA has been carried out by the Seabird Ecology Lab, in close collaboration with ANSE, from June to September of 2020. The field campaigns were conducted by different teams in several autonomous communities: Balearic Islands, Valencian Community, Region of Murcia, Andalusia and Canary Islands (Figure 1). We have obtained abundant movement data during these campaigns, which will allow us to perform the analyses needed to achieve the objectives of AMARYPESCA.
During the field campaigns we have worked with different seabird species: Cory’s shearwater (Calonectris borealis), Scopoli’s shearwater (Calonectris diomedea), European storm petrel (Hydrobates pelagicus and Hydrobates p. melitensis) and Bulwer’s petrel (Bulweria bulwerii) (Figures 2, 3 and 4, respectively). Moreover, we are still collecting movement data from European shags (Gulosus aristotelis) and yellow-legged gulls (Larus michahellis) equipped with GPS/GSM transmitters (Figures 5 and 6) between January and April of the present year in the Balearic Islands and Murcia. Preliminary results on the movement and use of different habitats by these species can be found in a post below.
We have used different tracking devices to assess the use of RAMPE by seabirds and to investigate the interactions among seabirds, fishing vessels and fish farms. Global Positioning System (GPS) tracking devices can provide the location of tagged individuals with a very high temporal and spatial resolution. Some of these devices can also measure the acceleration of the animal and detect direct interactions with radars from fishing vessels. If the tracking devices use Global System for Mobile communications (GSM) technology, we can receive all data via the mobile communications network, virtually in real-time. Otherwise, we need to retrieve the devices after a few days and up to a month after the deployment to obtain the movement data collected by them. Check Figure 7 to see the deployment process of a GPS tracking device on the back of a Scopoli’s shearwater, and Figures 5, 6, 8, 9 and 10 to see several of the devices we used depending on the species behavioural and morphological traits.
In addition to GPS tracking devices, we have also deployed Global Location Sensing (GLS) devices, or light-level geolocators (Figure 11), on a selection of individuals tagged with GPS tracking devices. Geolocators are used to study large-scale migratory movements, but they also measure the conductivity of salt water, providing useful information on whether the animals are in contact with sea water. Thus, we can infer the activity of seabirds based on the wet or dry state of the geolocator: resting on the water (geolocator wet), flying (geolocator dry) or foraging (frequent shifts in wet-dry state).
In summary, we obtained 1004 foraging trips (round trips from the breeding colony) from 290 individuals (all species) during the fieldwork developed from June to September of 2020. Out of the total amount of trips, 244 were obtained during the incubation period and 537 were obtained during the chick rearing period (Figures 12 and 13). Table 1 includes the number individuals tagged and foraging trips per species, breeding colony breeding phase. Foraging movements from all the studied seabirds cover a wide area of the Mediterranean Sea and the Atlantic Ocean, in addition to the coasts belonging to several Spanish autonomous communities and different countries in Africa.
All the movement-related data collected from the different seabirds studied here will allow us to perform a detailed spatio-temporal analysis that will help in characterising the interactions among seabirds, fishing vessels and fish farms, identifying the drivers of these interactions, and determining the most dangerous situations for seabirds. Moreover, these analyses will also enable us to propose measures to improve the management of RAMPE and of human activities at sea, which would ultimately allow a sustainable exploitation of the marine environment that minimises the adverse impact on seabirds.
World Oceans Day
Seabirds and the Network of Marine Protected Areas
8th June 2020
Seas and oceans are one of the most unknown and at the same time most fascinating ecosystems on the planet. However, growing human activities in the marine environment are rapidly accelerating their deterioration. As a result, many countries are increasing the surface of their marine protected areas. In Spain, the figure of Marine Protected Area has existed since 2007 (Law 24/2007 on Natural Heritage and Biodiversity), and in 2010 the Network of Marine Protected Areas was formally created (RAMPE, law 41/2010 on the protection of the marine environment) with the aim of carrying out a coherent management of the marine environment in order to achieve a good environmental status. In 2014, 39 special protection areas for birds from the Natura 2000 Network became part of the RAMPE. Despite this, only around 13% of Spanish waters are currently under some form of protection, and many of them still do not currently have management plans that consider such important aspects as interactions between seabirds and fisheries or aquaculture.
Seabirds are top predators, meaning that they are found in the upper levels of marine trophic networks. This advantageous position makes them sensitive to most alterations in the marine ecosystem, making them sentinel species of the seas and oceans health. In addition, seabirds live at the interface between the marine and terrestrial environments, feeding at sea and returning to land to rest, nest and rear their chicks, allowing us to study them with relative ease. One of the most important information we can get from seabirds is their at-sea distribution, the areas they use to feed and to find food for their chicks. This information, combined with diet and ecotoxicology studies helps us to know the environmental quality of the different marine regions, as well as the health of fishing stocks. The most practical and accurate method for obtaining this information is the deployment of remote tracking (GPS) devices, which can record and transmit their movements at intervals of up to less than a minute through the mobile phone network.
Currently, our research group (Seabird Ecology Group) of the Faculty of Biology and the Institute for Research on Biodiversity (IRBIo) of the Universitat de Barcelona, in collaboration with the Asociación de Naturalistas del Sureste (ANSE), are developing two projects with the support of Fundación Biodiversidad from the Ministry for the Ecological Transition and the Demographic Challenge, and also in collaboration with the Spanish Institute of Oceanography (IEO). The objectives of both projects are linked to the actions of LIFE INTEMARES, which pursue the effective management of marine areas within the Natura 2000 network, with the active participation of the involved sectors and research as main tools for decision making.
The project “AMARYPESCA: Las aves marinas como instrumento para la mejora de la gestión pesquera y acuícola en el contexto de una RAMPE sostenible” (seabirds as a tool to improve the management of fisheries and aquaculture in the context of a sustainable RAMPE)", in the framework of the 2019 call of the Pleamar Program, co-financed by the European Maritime and Fisheries Fund, aims at knowing the role that the current RAMPE plays in the conservation of seabirds, in addition to investigating the interactions between seabirds and fishing and aquaculture activities, in order to improve the management of RAMPE and human activities at sea.
Along the same lines, the project "GAUDIN: La gaviota de Audouin como instrumento para la mejora de la gestión de la RAMPE en el Levante español” (The Audouin's gull as a tool for improving the management of RAMPE in Spain’s east coast”, in the framework of the call for proposals for the conservation of marine biodiversity in Spain 2019 of the Fundación Biodiversidad of the Ministry for Ecological Transition and Demographic Challenge, seeks to know the role of the current RAMPE in the conservation of Audouin's gull (Ichtyaetus audouinii) and characterize the interactions between these birds and fishing vessels.
To achieve these goals, we have placed several GPS devices in seabirds of different species: the European shag (Gulosus aristotelis) and the yellow-legged gull (Larus michahellis) as part of the AMARYPESCA project, and the Audouin's gull as part of the GAUDIN project.
In the following map you can see the trips of all the individuals marked with GPS devices of European shag (orange) in Isla Grosa (Murcia) and Illa de l’Aire (Balearic Islands), and of yellow-legged gull (blue) and Audouin’s gull (yellow) in San Pedro del Pinatar (Murcia), registered from the time of its placement until the end of May.
Of the three species instrumented with GPS to date in the Spain’s east coast, we first worked with the European shag. This seabird, which nests in areas of rocky cliffs, is listed as a vulnerable species in the Spanish Catalog of Threatened Species, as it is threatened by bycatch, overfishing and marine pollution.
The ANSE team, partners in the AMARYPESCA project, carried out the fieldwork in January and February, deploying GPS devices in a total of eight adult birds, mostly breeders, from Isla Grosa (Murcia) and Illa de l’Aire (Balearic Islands).
European Shag (Gulosus aristotelis) equipped with a GPS/GSM device. Picture credit: ANSE.
The spatial ecology of this species is still quite unknown, and we hope that the results we are obtaining with this project can contribute to its knowledge. On the map above you can see how Isla Grosa’s European shags often move north, approaching and possibly interacting with fish farms. Instead, we can observe that the individuals of Illa de l’Aire move near the coasts of the islet, as well as Menorca and Mallorca. Here you can see in detail the latest movements of individuals equipped with GPS devices.
Next, we worked with the yellow-legged gull, a seabird with mostly coastal habits, with great foraging strategy adaptability. Thanks to these generalist attributes, it has adapted in an extraordinary way to take advantage of trophic resources derived from human activity, such as the food available in landfills or from fisheries discards. This association with anthropogenic habitats has made their populations grow exponentially throughout its range, and it has very abundant breeding populations throughout the coast. ANSE staff deployed 17 GPS devices in adult breeding individuals from San Pedro del Pinatar (Murcia).
Yellow-legged gull (Larus michahellis) equipped with a GPS device. Picture credit: Antonio Zamora.
The first results obtained support this change in diet towards anthropogenic food subsidies, mainly of terrestrial origin (landfills, waste treatment centers, crop fields and irrigation ponds ...). In addition, the trips they make at sea seem to be linked to possible interactions with fisheries discards and fish farms. Here you can see the latest movements of individuals equipped with GPS.
The last species we have worked with is Audouin's gull. This species is endemic to the Mediterranean and cataloged as vulnerable in the Spanish Catalog of Threatened Species. The Spain’s east coast is home to the most important breeding populations of the entire species. Its main current threats are bycatch, dependence on fisheries discards and marine pollution.
A field team from ANSE and the Universitat de Barcelona deployed seven GPS devices in breeding adult Audouin’s gulls from San Pedro del Pinatar (Murcia).
Deploying a GPS device (using a harness) on an Audouin's gull (Ichtyaetus audouinii). Picture credit: Raquel Castillo Contreras.
The results obtained so far demonstrate that this species also makes extensive use of land resources of anthropogenic origin, including those available in urbanized areas and cultivated fields. However, our preliminary results show that part of the population specializes in feeding in marine habitats, often taking advantage of fishing discards. Here you can see the latest movements of Audouin's gulls equipped with GPS.
Finally, it is worth highlighting the importance of these results, albeit still preliminary, towards the achievement of the objectives of both projects. A better understanding of the spatial ecology of seabirds and their interactions with fisheries and fish farms, adding to the equation the limits of the current RAMPE, will allow us to understand the role that the current RAMPE has in the conservation of seabirds. This will help improve the management of RAMPE and of fishing and aquaculture production activities so that human activities and marine birds can coexist.