Alejandro Bortolus

Educational Background

Doctor of Biological Sciences. 2001. Universidad Nacional de Mar del Plata, Argentina.
Licenciado of Biology (=Master). 1996. Universidad Nacional de Mar del Plata, Argentina

Shorebird flocks usually use the open high marshes to rest, and prey upon fiddler crabs intensely.

Research Interest

Starting my career as a field ecologist focused on plant–animal interactions in estuarine environments, I became interested in ecosystem and community ecology of coastal environments, biological invasions, macroecology and environmental management and conservation. Even though I spend most of my time doing practice rather than theory, I am also very interested on the structure of biological theories, the standards of biological explanation, and the ways in which biological theories are tested today.

Spartina alterniflora bed (to the left) in a New England cobble beach where experimental transplants are being conducted to evaluate competition with neighbor species.

As a postdoc in Bertness’ lab at Brown I have focused my attention to study some associations of fauna and flora so similar among distant regions worldwide that they were historically assumed to be the caused by the same processes. I have found that the causal processes for these “sibling patterns” are likely to be determined by local environmental conditions rather than by a globally unique factor. Sibling patterns do not necessarily involve several species, for the pattern of distribution of a single species in different regions may be also misinterpreted when it is a product of the convergence of different ecological processes taking place in different sites and regions. It is important to recognize and identify what those mechanisms are in order to optimize our understanding of nature and its conservation. This research will bring interesting and innovative perspectives and solutions to environmental conservation issues of global concern.

The high marshes of Sapelo Island, Georgia, present an strong association between fiddler crabs (Uca spp.) and halophytes (e.g., Salicornia spp.). The distribution of crabs is normally overlapped by plants’ distribution. This ecological pattern is identical to that found in Mar Chiquita (province of Buenos Aires, Argentina). However, the causal processes seem to be different for each region. A different balance between negative and positive interactions seems to converge to an identical pattern of plant-animal association in marshes of Sapelo and Mar Chiquita.

Experiments with manipulation of light intensity, plant cover and crab presence deployed at Sapelo Island, Georgia to study the association between halophytes and the dominant two species of fiddler crabs (Uca pugnax and Uca pugilator).

The distribution of Spartina alterniflora in New England’s cobble beaches, where this species forms monospecific beds in the lower part of the intertidal, shows an amazing similarity with the distribution of this species in regular salt marshes. However, while in the later the distribution of S. alterniflora seems mainly determined by competition with its congener S. patens, there is not evidence that this negative interaction exist in the cobble beaches (where S. patens is hardly found).

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