New Publication on Storm Petrel Ecology!

Ramírez, F., Afan, I., Tavecchia, G., Catalán, I. A., Oro, D. and Sanz-Aguilar, A. 2016 Oceanographic drivers and mistiming processes shape breeding success in a seabird. Proceedings of the Royal Society B. Doi: 10.1098/rspb.2015.2287

Photo: M. Gomilla

Abstract: Understanding the processes driving seabirds' reproductive performance through trophic interactions requires the identification of seasonal pulses in marine productivity. We investigated the sequence of environmental and biological processes driving the reproductive phenology and performance of the storm petrel (Hydrobates pelagicus) in the Western Mediterranean. The enhanced light and nutrient availability at the onset of water stratification (late winter/early spring) resulted in annual consecutive peaks in relative abundance of phytoplankton, zooplankton and ichthyoplankton. The high energy-demanding period of egg production and chick rearing coincided with these successive pulses in food availability, pointing to a phenological adjustment to such seasonal patterns with important fitness consequences. Indeed, delayed reproduction with respect to the onset of water stratification resulted in both hatching and breeding failure. This pattern was observed at the population level, but also when confounding factors such as individuals' age or experience were also accounted for. We provide the first evidence of oceanographic drivers leading to the optimal time-window for reproduction in an inshore seabird at southern European latitudes, along with a suitable framework for assessing the impact of environmentally driven changes in marine productivity patterns in seabird performance.

Official press release (Spanish) here

New publication : a new term in evolutionary biology and paleontology

Martinez-Abrain, A. 2015 Stoch-aptation: a new term in evolutionary biology and paleontology. Ideas in Ecology and Evolution. doi:10.4033/iee.2015.8.6.n

Following two seminal papers published in the journal Paleobiology by Stephen Jay Gould and Elisabeth Vrba several decades ago, I suggest a new term (stoch-aptation) to refer to those individual traits or sets of traits that provide, just by chance, fitness adventages to species when faced with catastrophes (i.e. geological events triggering massive mortality), and that may lead to the origin of taxonomical entities above the species level.

Photo from http://www.aqua.org/explore/animals/chambered-nautilus

I provide as an example of stoch-aptations the set of features that helped mammals pass the Cretaceous-Paleogene transition, as well as traits behind the success of living fossils. However, the identification of specific stoch-aptations can be difficult. This missing term is necessary and useful to (a) consolidate the idea of selection at different hierarchical levels, (b) acknowledge the role of chance in the evolution of higher taxonomical categories and (c) think of the role of geological catastrophes as generators of innovation.

New publication on seabirds !

Steigerwald, E., Igual, J.-M., Payo-Payo, A., and Tavecchia G. Effects of decreased anthropogenic food availability on an opportunistic gull: evidence for a size-mediated response in breeding females Ibis in press

Photo: G. Tavecchia

Some opportunistic vertebrates exploit, and may largely rely upon, food generated by human activities. Better understanding the influence of this additional anthropogenic food on species’ ecology would inform sustainable waste management. In the Balearic Archipelago of Spain, closure of an open-air landfill site provided an experimental setting to measure the effect of removing anthropogenic food on the average body mass, breeding parameters and body condition of opportunistic Yellow-legged Gulls Larus michahellis. After landfill closure there was a significant decline in the average body mass of breeding females and males (-10.4% and -7.8%, respectively), in average egg volume (-4.8%), and a shift in the modal clutch size from 3 to 2 eggs. Body condition decreased after landfill closure in both sexes. In breeding females, the drop in body weight was greater for birds with a low body size index. The differential response to a reduction of anthropogenic food between small and large birds suggests that food of anthropogenic origin contributes to temper the effects of natural selection, making the long-term demographic effects of changes in food supply difficult to predict.

New Publications !!

Rivas, M., Santidrián Tomillo, P., Diéguez Uribeondo, J. and Marco, A. Leatherback hatchling sea-finding in response to artificial lighting: Interaction between wavelength and moonlight.

© Dawn Witherington | DrawnbyDawn.com

Over the last decades, growing human populations have led to the rising occupation of coastal areas over the globe causing light pollution. For this reason, it is important to assess how this impact threatens endangered wildlife. Leatherback turtles (Dermochelys coriacea) face many threats of anthropogenic origin including light pollution on nesting beaches. However, little is known about the specific effects. In this study we studied the effect of different light wavelengths (orange, red, blue, green, yellow and white lights) on hatchling orientation under the presence and absence of moonlight by analyzing: (i) the mean angle of orientation, (ii) crawling duration, and (iii) track patterns. Hatchling orientation towards the sea was always better under controlled conditions. In the absence of moonlight, leatherback hatchlings were phototaxically attracted to the experimental focus of light (misoriented) for the colours blue, green, yellow and white lights. Orange and red lights caused a lower misorientation than other colors, and orange lights produced the lowest disrupted orientation (disorientation). On nights when moonlight was present, hatchlings were misorientated under blue and white artificial lights. Crawling duration was low for misoriented hatchlings and high for the disoriented individuals. Our conclusion to this is that hatchlings can detect and be impacted by a wide range of the light spectrum and we recommend avoiding the presence of artificial lights on nesting beaches. Additionally, actions to control and mitigate artificial lighting are especially important during dark nights when moonlight is absent

Journal of Experimental Marine Biology and Ecology 463 (2015) 143–149

Dornfeld, T, Robinson, N. J, Santidrián Tomillo, P., Paladino,  · Frank V. Ecology of solitary nesting olive ridley sea turtles at Playa Grande, Costa Rica

© Dawn Witherington | DrawnbyDawn.com

Olive ridley turtles (Lepidochelys olivacea) have two distinct mating systems: independent (solitary) and synchronized and mass assemblages (arribadas). Arribada nesting beaches have been the focus of most research, even though solitary nesting is the most common behavior. The purpose of this study was to assess the contribution of solitary nesting turtles to the olive ridley turtle population. We studied the nesting ecology of solitary nesting olive ridley turtles within the national park Parque Nacional Marino Las Baulas (PNMB) in Playa Grande, Costa Rica (10°20′N, 85°51′W) and compared these turtles to nearby arribada turtles. Between 2009/2010 and 2013/2014, an estimated 933 nesting activities occurred within PNMB. This number of turtles has not changed significantly since 1995. During this study, 285 females were tagged; of these, 30 females were encountered nesting on more than one occasion. Significantly, more females emerged (31.1 % of tracks) during the third-quarter moon, often a predictor. of arribada events, than any other moon phase. However, there was no significant change in nesting activity at PNMB during nearby arribada events. Mean hatching success (78.5 ± 23.4 % SD) was higher, and incubation temperatures were lower (ranging from 28.3 to 33.4 °C) than at nearby arribada beaches. Thus, clutches are relatively successful and may produce males. These data suggest that solitary olive ridley turtles are important. Currently, PNMB protects turtles from October to March; however, hatching success was highest and 40 % of nesting activity occurred during the rainy season (August–November). More turtles could be protected by increasing the temporal scope of park protection.

Marine Biology: DOI 10.1007/s00227-014-2583-7

Fledgling !!

It is time for young Scopoli´s shearwater to leave their nests. 

They will go to the open ocean, for the first time, and possibly they will be back to breed in 4 to 7 years. 

Have a nice journey !!!!

New Publication !

Sergio, F., Taferna A., De Stephanis, R., López Jiménez, L., Blas, J., Tavecchia, G., Preatoni, D., and Hiraldo, F., 2014: 'Individual improvements and selective mortality shape lifelong migratory performance'. Nature. doi:10.1038/nature13696

Billions of organisms, from bacteria to humans, migrate each year and research on their migration biology is expanding rapidly through ever more sophisticated remote sensing technologies. However, little is known about how migratory performance develops through life for any organism. To date, age variation has been almost systematically simplified into . These comparisons have regularly highlighted better migratory performance by adults compared with juveniles, but it is unknown whether such variation is gradual or abrupt and whether it is driven by improvements within the individual, by selective mortality of poor performers, or both.

Here we exploit the opportunity offered by long-term monitoring of individuals through Global Positioning System (GPS) satellite tracking to combine within-individual and cross-sectional data on 364 migration episodes from 92 individuals of a raptorial bird, aged 1–27 years old. We show that the development of migratory behaviour follows a consistent trajectory, more gradual and prolonged than previously appreciated, and that this is promoted by both individual improvements and selective mortality, mainly operating in early life and during the pre-breeding migration. Individuals of different age used different travelling tactics and varied in their ability to exploit tailwinds or to cope with wind drift. All individuals seemed aligned along a race with their contemporary peers, whose outcome was largely determined by the ability to depart early, affecting their subsequent recruitment, reproduction and survival. Understanding how climate change and human action can affect the migration of younger animals may be the key to managing and forecasting the declines of many threatened migrants.

See also at IMEDEA (CSIC-UIB) and IMEDEA Divulga here 

New Publication

Sergio,F., Schmitz, O. J., Krebs, C.J., Holt, R.D., Heithaus, M. R., Wirsing, A. J., Ripple, W. J., Ritchie, E., Ainley, D., Oro, D., Jhala, Y.,Hiraldo, F. and Korpimmäki, E. 2014 .Towards a cohesive, holistic view of top predation: a definition, synthesis and perspective Oikos, DOI: 10.1111/oik.01468

Research on the ecology of top predators – upper trophic level consumers that are relatively free from predation once they reach adult size – has provided regular contributions to general ecology and is a rapidly expanding and increasingly experimental, multidisciplinary and technological endeavour. Yet, an exponentially expanding literature coupled with rapid disintegration into specialized, disconnected subfields for study (e.g. vertebrate predators versus invertebrate predators, community ecology versus biological control etc.) increasingly means that we are losing a coherent, integrated understating of the role and importance of these species in ecosystems. This process of canalization is likely to hinder sharing of scientific discovery and continued progress, especially as there is a growing need to understand the generality of the top–down forcing, as demonstrated for some members of this group. Here, we propose ways to facilitate synthesis by promoting changes in mentality and awareness among specialists through increased debate and collaboration, conceptual reviews and a series of exemplary case studies. The strategy will rely on the collective contribution by all scientists in the field and will strive to consolidate and formalise top-order predation as a holistic, cohesive, cross-taxonomical field of research studying the ecology, evolution and behaviour of apex predators and their capability to exert top–down forcing on lower trophic levels. (Photo: F. Sergio)

New at the Population Ecology Group (GEP)

Giulia Bastianelli, student at the Unidad Mixta de Investigación en Biodiversidad (UO/CSIC/PA), joined the GEP for three months. Giulia is working on the influence of the altitudinal gradient on the demography of passerines.

The ecological detective in video

I had the opportunity recently to give a talk at the Universities of Vigo, Santiago and Coruña with the excuse of the presentation of my popular science book "El detective ecológico: reflexiones sobre historia natural". Despite the title of the book my reflections are on ecology, evolution and conservation biology although directly inspired by the observation of the natural world in the field. I did not cover exactly the content of the book in my talks, not to upset would be readers, but I talked about some of my main interests and concerns in these three big fields. You may listen and watch the entire conference if you please under the following:

LINK TO THE TALK

LINK TO QUESTIONS FROM THE PUBLIC

The video was recorded at the University of Vigo and I thank Xose Holgado for his good work with this. I am also thankful to Dr. Alberto Velando for organizing the talk.

(Alejandro Martínez-Abraín, PhD)