Institut d'Ecologia Aquàtica (IEA)http://hdl.handle.net/10256/43962024-03-29T01:09:31Z2024-03-29T01:09:31ZConservation biology of the Spanish toothcarp (Aphanius iberus): mechanisms of coexistence with eastern mosquitofish (Gambusia holbrooki)Fernández-Vilar, Andrés Lucashttp://hdl.handle.net/10256/238272023-12-12T08:56:06Z2023-07-10T00:00:00ZConservation biology of the Spanish toothcarp (Aphanius iberus): mechanisms of coexistence with eastern mosquitofish (Gambusia holbrooki)
Fernández-Vilar, Andrés Lucas
Inland waters are amongst the most diverse and impacted ecosystems globally, and they
host many endangered taxa. Cyprinodontiforms are at the forefront of endangered freshwater
fishes in Europe, with more than 80% of the species of this taxon considered threatened by the
IUCN. The Aphaniidae, belonging to that order, are mostly distributed in the Mediterranean
coastal areas, where ecosystems face many environmental pressures. This thesis consists of
three main studies: (i) an analysis of the drivers and predictors of population extirpations of the
Spanish toothcarp, Aphanius iberus; (ii) an adaptation and performance assessment of an
underwater stereo-video system (also referred to as SVS) for studying the ecology of the fish
assemblages of coastal lagoons, with emphasis on the endemic Spanish toothcarp and the
invasive mosquitofish (Gambusia holbrooki); and (iii) a study, using the new SVS system, of diel
and seasonal microhabitat partitioning between the endangered toothcarp and the invasive
mosquitofish in relation to variation in limnological features.; Les aigües continentals es troben entre els ecosistemes més diversos i impactats a nivell
global alhora que acullen moltes espècies amenaçades. Els ciprinodontiformes són els peixos
continentals europeus amb més risc d'extinció, amb més del 80% de les espècies considerades
amb algun grau d'amenaça per la IUCN. La família Aphaniidae, que pertany a aquest grup, es
distribueix principalment en aigües continentals de zones costaneres de la Mediterrània, on els
ecosistemes suporten moltes pressions ambientals. Aquesta tesi consta de tres estudis
principals: (i) anàlisi de causes i predictors d’extirpació de poblacions del fartet Aphanius iberus;
(ii) adaptació i avaluació del rendiment d'un sistema vídeo estèreo (stereo-video system, SVS)
per estudiar l'ecologia de peixos a llacunes costaneres, amb èmfasi en el fartet endèmic i la
l’espècie invasora gambúsia, Gambusia holbrooki; i (iii) estudi de la partició del microhàbitat
circadiana i estacional entre el fartet i la gambúsia, utilitzant el nou SVS i mesurant
característiques limnològiques.
2023-07-10T00:00:00ZImportance of life history traits for vulnerability to climate change: implications for macroalgal restorationCaralt, Sònia deVerdura Brugarola, JanaSantamaría Pérez, JorgeVergés Guirado, AlbaCebrian Pujol, Emmahttp://hdl.handle.net/10256/237692024-02-28T10:00:45Z2023-11-23T00:00:00ZImportance of life history traits for vulnerability to climate change: implications for macroalgal restoration
Caralt, Sònia de; Verdura Brugarola, Jana; Santamaría Pérez, Jorge; Vergés Guirado, Alba; Cebrian Pujol, Emma
Fucalean algae are dominant canopy-forming species that create extensive and highly productive ecosystems in the intertidal and subtidal rocky shores of temperate seas. Regrettably, these marine forests are in decline due to various human drivers, with the Mediterranean Sea one of the most threatened areas. To design appropriate restoration strategies adapted to cope with the unavoidable change in future climate conditions, the response to climate change of the candidate species must be considered. It is important to assess how the specific life history traits of the foundational species may determine environmental requirements, and thus responses to future climate change. This knowledge will allow us to predict the potential winners and losers among the species potentially inhabiting the same areas in a future context of global climate change, providing important information to fine-tune future restoration interventions. The aim of this study was to evaluate the response of two canopy-forming species inhabiting similar upper subtidal zones but with different life history traits to a combination of anomalous high temperatures and increased UV radiation. One of the species (Ericaria crinita) was perennial, slightly exposed rocky shores and dwelling in areas where extreme temperatures can be frequent; while the other (Ericaria mediterranea) a semi-perennial species that dwells in wave-exposed zones, with seawater temperatures buffered by the high hydrodynamism. Our results show that the effects of temperature and radiation are species- (mediated by the species life history traits) and life-stage specific. High temperatures strongly affected the adults of both species, especially E. mediterranea. The germlings in addition to being very susceptible to high temperatures, were also vulnerable to UV radiation, exacerbating the impacts of temperature, especially on E. crinita recruits. Interestingly, vulnerability to climate-driven impacts was determined by the specific life history traits, with i) the species dwelling in open areas the most sensitive to warming and, ii) the perennial species the most vulnerable to UV radiation. Last, we discuss how these species-specific responses to climate-driven impacts may be key in terms of species that could foster the resistance and resilience of marine ecosystems to future climate impacts
2023-11-23T00:00:00ZTwo centuries of spatial and temporal dynamics of freshwater fish introductionsMuñoz-Mas, RafaelEssl, FranzKleunen, Mark vanSeebens, HannoDawson, WayneCasal, Christine Marie V.García-Berthou, Emilihttp://hdl.handle.net/10256/235472023-10-27T09:45:05Z2023-09-01T00:00:00ZTwo centuries of spatial and temporal dynamics of freshwater fish introductions
Muñoz-Mas, Rafael; Essl, Franz; Kleunen, Mark van; Seebens, Hanno; Dawson, Wayne; Casal, Christine Marie V.; García-Berthou, Emili
Aim
Investigating major freshwater fish flows (translocations) between biogeographic regions and their temporal dynamics and also quantifying spatial patterns and temporal changes in the array of introduced species, and the emergence and distance between major donor and recipient regions.
Location
Global.
Time Period
1800–2020.
Major Taxa Studied
Freshwater fishes.
Methods
We analysed a global dataset on freshwater fish introductions (4241 events of 688 species). Freshwater fish flows were investigated with flow diagrams and χ2 tests, while PERMANOVA (permutational multivariate analysis of variance) was used to test the association between species and regions and temporal shifts. Cluster analysis revealed major recipient areas and composition of the introduced species. Finally, changes in distances between donor and recipient sites were tested with PERMANOVA.
Results
The number of introductions between biogeographic regions mirrored the European and North American dominance before World War II (WWII) and the trends in recreational fishing, biocontrol programmes and food production, especially in the Sino-Oriental region, which has a long tradition of aquaculture and fishkeeping. Over the years, the origins and composition of introduced species changed uniquely in each biogeographic region, although the most introduced species are common to every region. Salmonids and other cold-water species were frequently introduced before the 1950s, whereas tropical ornamental and aquaculture species currently prevail. Distances between donor and recipient sites did not vary over the time. After WWII, the Sino-Oriental region consolidated its dominance and the Ethiopian and Neotropical regions emerged as new global donor and recipient regions.
Main Conclusions
Global policy should focus on tropical ornamental and aquaculture species, which could benefit from global warming, especially in the Sino-Oriental region, because it currently dominates freshwater fish species flows, and the Ethiopian and Neotropical regions, because they recently emerged as important global donor and recipient regions of freshwater fish introductions
2023-09-01T00:00:00ZVariability in the health status and reproductive traits of European sardine stocks in the Mediterranean. Implications for fishery managementCaballero-Huertas, Martahttp://hdl.handle.net/10256/233912023-10-04T05:57:00Z2023-05-26T00:00:00ZVariability in the health status and reproductive traits of European sardine stocks in the Mediterranean. Implications for fishery management
Caballero-Huertas, Marta
Small pelagic fish play an important ecological role mainly due to their contribution in transferring energy from low to higher trophic levels. Likewise, the capture of these species is in many cases an important nutritional and economic source for many nations. In these respects, one of the most relevant pelagic species is the European sardine (Sardina pilchardus) throughout its distributional range, in the North and Central-Eastern Atlantic, from the North Sea to the Senegalese coast, including the Mediterranean Sea, in which an alarming health status of the stocks has been registered during the last decades. Despite its importance, there are still many unanswered questions that try to explain its variability in the state of health along the different areas where it is found. Furthermore, and due to the decline in captures, biomass and body condition (i.e., individual energy reservoirs) of the resource, it has been suggested that the effect of global change, overfishing, pollution or parasitism, and/or the interaction among factors could be behind it. This thesis has been enthusiastically carried out with the aim of shedding light on the current health status of the European sardine along the Mediterranean, highlighting the assessment of the state of condition (closely related to the annual reproductive cycle), as well as on determining the likely factors that shape its spatial and, potentially, temporal variability in this regard. The confluence of genetic, physiological and ecological information has been the central axis of this work, since it is essential to approach the study of this and other fishery resources from a holistic manner, especially if this information is to be applied to the field of fisheries administration and management; Els peixos pelàgics de mida petita tenen un paper ecològic important sobretot per la seva contribució en la transferència d'energia de nivells tròfics baixos a més alts. Així mateix, la captura d'aquestes espècies és en molts casos una important font nutricional i econòmica per a moltes nacions. En aquests aspectes, una de les espècies pelàgiques més rellevants és la sardina europea (Sardina pilchardus) en tota la seva distribució, a l'Atlàntic nord i centre-oriental, des del mar del Nord fins a la costa senegalesa, passant per la Mediterrània, en la qual s'ha registrat un estat de salut alarmant dels stocks durant les últimes dècades. Malgrat la seva importància, encara queden moltes preguntes sense resposta que intenten explicar la seva variabilitat a l’estat de salut al llarg de les diferents zones on es troba. A més, i a causa del descens de les captures, la biomassa i la condició (és a dir, els dipòsits d'energia dels individus) del recurs, es planteja que l'efecte del canvi global, la sobrepesca, la contaminació o el parasitisme, i/o la interacció entre factors podria estar al darrere. Aquesta tesi s'ha realitzat amb entusiasme amb l'objectiu de donar llum sobre l’estat de salut actual de la sardina europea al llarg del Mediterrani, destacant l’avaluació de la condició (estretament relacionat amb el cicle reproductiu anual), així com per a determinar els factors que configuren la seva variabilitat espacial i, potencialment, temporal en aquest aspecte. La confluència d'informació genètica, fisiològica i ecològica ha estat l'eix central d'aquest treball, ja que és fonamental abordar l'estudi d'aquest i d'altres recursos pesquers des d'una manera holística, sobretot si aquesta informació es vol aplicar a l'àmbit de l'administració i gestió pesquera
2023-05-26T00:00:00Z