2014 DEPARTAMENTO DE CIÊNCIAS DA VIDA FACULDADE DE CIÊNCIAS E TECNOLOGIA UNIVERSIDADE DE COIMBRA Using a seabird top predator to assess the adequacy of the Berlengas Marine Protected Area adequacy of adequacy the Berlengas Marine Protected Area the Berlengas Using a seabird top predator a the to assess Using Joana Sofia Costa Neves Pais de Faria 2014 Joana de Faria Pais DEPARTAMENTO DE CIÊNCIAS DA VIDA FACULDADE DE CIÊNCIAS E TECNOLOGIA UNIVERSIDADE DE COIMBRA Using a seabird top predator to assess the adequacy of the Berlengas Marine Protected Area Dissertação apresentada à Universidade de Coimbra para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Ecologia, realizada sob a orientação científica do Professor Doutor Jaime Albino Ramos (Universidade de Coimbra) e do Doutor Vítor Hugo Paiva (Universidade de Coimbra). Joana Sofia Costa Neves Pais de Faria 2014 Acknowledgements First and foremost, I would like to express my sincere gratitude to my dedicated supervisors Professor Jaime Albino Ramos and Vítor Hugo Paiva for all the guidance, support, patience, reviews and of course for all the moments of good disposition. I want to particular highlight all the great technical support provided by Vítor in all the technology and software that was new to me, thank you for your precious help. It is with a smile that I remember all the days passed in Berlenga island, where the wild beauty, distant from all the civilization’s noise make possible to any visitor to forget all the world preoccupations and absorb its peaceful beauty. But even better is to remind all the great persons that I met in that island, thank you Elisabete, Mourato, Paulo for receiving us so well and always with a smile. Also thank you Rahel for being my travel companion and for capturing on photo all the great moments of fieldwork, joy and laugh. A truly thank you to all my friends and family, especially to my mother for always providing everything she had, only to make her beloved children happy. (“Querida mãe, estarei eternamente grata por tudo o que fizeste e continuas a fazer por mim e por todo o imenso amor que só uma mãe pode dar!”). To my dear brother, I want to thank you for always being there for me and for being my “writing coach”, always giving me strength and motivation for keep going with the writing work. And last, but surely not least, I want to thank to my “Soulmate” for all the love and support, for always being there for me, believing in me and for the encouraging me in the difficult moments. I hope we can have a wonderful happy life together. Off course, I also want to thank his great family for always having me treated like a family member and for all the love and affection. Table of contents Abstract ............................................................................................................................. 5 Resumo ............................................................................................................................. 7 List of Tables .................................................................................................................... 9 List of Figures ................................................................................................................. 10 Chapter 1 - Introduction ................................................................................................. 11 Chapter 2 - Methods ....................................................................................................... 17 2.1. Study area ................................................................................................................ 18 2.1.1. The marine surroundings of Berlenga Island ....................................................... 21 2.2. Study species ........................................................................................................... 23 2.3. GPS-loggers: deployment and specifications .......................................................... 24 2.4. GPS tracking data analyses...................................................................................... 25 2.4.1. Trip filtering ......................................................................................................... 25 2.4.2. Kernel analysis ..................................................................................................... 26 2.5. Environmental data .................................................................................................. 27 2.6. Species distribution modelling (SDM) .................................................................... 29 2.7. The Zonation algorithm ........................................................................................... 31 2.8. Data analysis ............................................................................................................ 31 Chapter 3 – Results ......................................................................................................... 33 3.1. Seasonal and inter-annual differences in foraging patterns ..................................... 34 3.2. Species Distribution Modelling (SDM) of a pelagic marine predator..................... 38 3.3. Overlap between usage of at-sea areas by birds and the Berlengas mIBa and MPA areas ............................................................................................................................ 43 3.4. Conservation aspects ............................................................................................... 43 Chapter 4 – Discussion ................................................................................................... 45 4.1. Inter-annual and within season foraging patterns .................................................... 46 4.2. Habitat use and foraging segregation ...................................................................... 48 4.3. Management considerations .................................................................................... 50 References ...................................................................................................................... 52 Abstract Marine ecosystems have been facing an increasing number of threats such as unsustainable exploitation of marine resources (e.g. overfishing), degradation and loss of marine habitats, pollution, invasive species and climate change. A possible way to diminish the impact of such threats is through the establishment of Marine Protected Areas (MPAs), which play an important role in biodiversity conservation and contribute to restock the entire marine environment. However the percentage of ocean that are already protected (2.8%) is alarmingly low considering one of the targets set by the Convention on Biological Diversity (CBD): to protect at least 10% of coastal and marine areas until 2020. Berlengas archipelago surrounding waters have great conservation value due to features that congregate a high marine productivity, allowing the survival and maintenance of several seabird species, some of them endangered (e.g. the Balearic shearwater Puffinus mauritanicus). Although this important area is currently under protection, the boundaries of the Berlengas Marine Protected Area (MPA) do not overlap fully with the Berlengas marine Important Bird Area (mIBA), which was designated based on the areas with great importance to the small range local biodiversity. The present boundaries of the Berlengas MPA were defined with the contribution of tracking information of the most important foraging areas of a wide range seabird top predator, the Cory’s shearwater Calonectris diomedea, mostly during the chick-rearing phases of 2005 – 2008. Yet, the boundaries of the Berlengas mIBA and MPA have not been assessed, using tracking information for the whole breeding cycle of this species during several years (in order to take into account inter-annual environmental stochasticity). The aim of this thesis was to use tracking data of a seabird top predator to define boundaries of key foraging grounds and assess their adequacy on the establishment of a network of Marine Protected Areas within Mainland Portugal. More specifically, this work intended to answer the following questions: (1) Which factors (environmental or Human-related) drive the foraging distribution of Cory’s shearwater along the breeding period and across years? (2) Are the current boundaries (from both Berlengas mIBA and Berlengas MPA areas) protecting all key foraging grounds of this species? To address these questions Global Positioning System (GPS) tracking devices were attached to the back feathers of Cory’s shearwater in order to identify the foraging areas used by this species. Species Distribution Models (SDM; MaxEnt) were performed using foraging tracking data combined with environmental 5 data in order to understand which environmental variables trigger the foraging distribution of the species. To better access the adequacy of the current Berlengas mIBA and MPA boundaries it was used the conservation planning software Zonation. This software can be used to design and evaluate Marine Protected Areas by producing different scenarios depending on specification of conservational priorities. Results showed very distinct foraging patterns in 2010 and 2012 comparing with 2011 and 2013 and also distinct foraging trip characteristics, with trips closer to the colony during chick-rearing periods. These annual differences may be related with climatic variation, as reflected by the North Atlantic Oscillation (NAO) index, with the