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Comodoro Rivadavia, Argentina

Putman R.,Keil House | Flueck W.T.,University of Basel | Flueck W.T.,Atlantida Argentina University
Animal Production Science | Year: 2011

It has been noted that the search for patterns in biology to assist our understanding, often leads to over-simplification. That is, we are satisfied with statements that 'the species as a rule does this' or, 'males of this species do that'. But within such generalisations are masked what are often important variations from that supposed norm and in practice there is tremendous variation in morphology, physiology, social organisation and behaviour of any one species. The focus on a supposedly mean optimal phenotype has diverted attention away from variation around that mean, which is regularly regarded as a kind of 'noise' stemming merely from stochastic effects, and thus irrelevant to evolution. Yet it is becoming increasingly clear that this variation is by converse extremely significant and of tremendous importance both to evolutionary biologists and to managers. Such intraspecific variation (IV) may be directly due to underlying genetic differences between individuals or populations within a species, but equally may include a degree of phenotypic plasticity whether as 'non-labile', traits which are expressed once in an individual's lifetime, as fixed characteristics inherited from the parents or as more labile traits which are expressed repeatedly and reversibly in a mature individual according to prevailing conditions. Recognition of the extraordinary degree of IV which may be recorded within species has important consequences for management of cervids and conservation of threatened species. We review the extent of IV in diet, in morphology, mature bodyweight, reproductive physiology, in population demography and structure (sex ratio, fecundity, frequency of reproduction) before also reviewing the striking variation to be observed in behaviour: differences between individuals or populations in ranging behaviour, migratory tendency, differences in social and sexual organisation. In each case we explore the factors which may underlie the variation observed, considering the extent to which variation described has a primarily genetic basis or is a more plastic response to more immediate social and ecological cues. © 2011 CSIRO. Source

Monjeau A.,Atlantida Argentina University
Natureza a Conservacao | Year: 2010

This essay examines several crossroads, paradoxes and controversies in conservation politics in Latin America: populated and non-populated protected areas, local versus global forces, and the role of the national government in making long-term, ecologically correct decisions versus short-term politically correct local decisions. Ecologically sound projects at a global scale, such as the maintenance of the ecosystems working order, exceed the lifetime of the present generation. In addition to this, as decisions in a particular area may have ecological consequences that go beyond the sphere of that area, the responsibility cannot be delegated to the local management level. Local consensus is essential to implement conservation goals on the ground, but it should never be opposed to global priorities, especially because this antagonism puts the ecosystem working order at risk. In this ranking, the hierarchical organization of the decision making process, from global to local, is crucial, so that the State retains its organizational role while working along with the local forces in their effort to implement conservation. © 2010 ABECO. Source

Flueck W.T.,National Council for Scientific Research | Flueck W.T.,Atlantida Argentina University | Flueck W.T.,University of Basel
Biological Invasions | Year: 2010

A recent review on exotic cervids concluded that deer introduced to Patagonia impacted habitat and native huemul deer Hippocamelus bisulcus. I evaluate these assertions and amend information about this South American case study. Categorizing deer along narrow characteristics may be too restrictive to allow accurate predictions about interactions. More effective is considering the magnitude of plasticity (behavioral, phenotypic, genetic). The dichotomy of native versus exotic deer masks situations where prevailing ecological conditions are far from 'native', such as absence of predators, and such results from artificial settings have limitations. Studies used to contrast effects on vegetation from exotic red deer (Cervus elaphus) versus native huemul did not analyze native deer and provided no data to support conclusions in the review. Huemul were concluded to have high trophic overlap with red deer whose diet, however, was determined in another habitat where the food item of supposed major overlap was absent, and suggesting that red deer might cause exploitation competition was not supported by cited data. There was no mention that huemul are foremost exposed to livestock rather than exotic deer. Concluding that exotic prey including red deer increase predator density resulting in increased predation of huemul (apparent competition), was not supported by cited studies. To the contrary, high-density puma (Puma concolor) could not prevent guanaco (Lama guanicoe) from increasing >13-fold, nor that huemul expanded into these sites. Not only were those studies opposite to conclusions in the review, but none had studied huemul nor predator population trends. Data from little known species like huemul should be used with reservations when aiming at generalizations. © 2009 Springer Science+Business Media B.V. Source

Flueck W.T.,National Council for Scientific Research | Flueck W.T.,Atlantida Argentina University | Flueck W.T.,University of Basel
Biological Invasions | Year: 2010

Releasing alien mammals was considered positive in the past, but impacts were recognized as important already decades ago. Himalayan tahr were introduced to New Zealand (NZ), resulting in overt damage and continuous government control programs. Existing laws could not prevent NZ exports, and Argentina imports of tahr, although NZ authorities recommended against these imports. National and provincial legislation was possibly too complex, contradictory or incomplete to be enforced, or had loopholes such that tahr were imported to Argentina (2000, 2006). The estimated population in 2008 was 400-450 tahr. As even common travel routes are used to cross national borders in South America illegally with live ungulates, and enterprises importing tahr have been intercepted for illegally transporting wild ungulates previously, there are substantial risks that tahr might be released to new sites. As huge areas lack natural barriers, landscapes are very similar to NZ environments successfully invaded by tahr, and eradication or control are unfeasible, the future of Himalayan tahr in South America now hinges solely on releases or escapes. Importantly, the 2006 import was to Andean foothills which is an ecological time bomb. Considering climates, history of invasiveness in NZ, and low required propagule pressure, tahr could perform from 34°-55°S along the Andes. NZ still has many illegal liberations, thus it would be more difficult to contain illegal liberations in Argentina. It calls for more leadership and better standards by exporting countries, especially if they had the chance to experience the consequences of having received the exotic species earlier. © Springer Science+Business Media B.V. 2009. Source

Flueck W.T.,CONICET | Flueck W.T.,Atlantida Argentina University | Smith-Flueck J.A.M.,Atlantida Argentina University
Animal Production Science | Year: 2011

A small group of European red deer (Cervus elaphus elaphus) was introduced into the foothills of the Andes in Patagonia in the early 1920s. This species adapted well to the habitat and climatic conditions in the area and presently may number over 100000 animals. Several indices commonly used to evaluate the fitness of a species in its environment indicate that red deer thrive under very favourable conditions in Patagonia; for example, body size, antler development, reproductive rates, herd health, and longevity are near the maximum described for the species. Furthermore, some local populations occur at densities much higher than encountered in their native ranges. The objective was to examine several biological enzyme systems to test for variance in protein polymorphism in comparison to populations of red deer in other parts of the world. The protein systems examined by electrophoresis in the plasma included: post-transferrin, transferrin, vitamin D binding protein, plasminogen, and complement component; and in the erythrocytes: hemoglobin, superoxide dismutase, glucose phosphate isomerase, and diaphorase I. Variation in plasminogen was lower than is typical for red deer, and glucose phosphate isomerase showed no variation. Furthermore, some occurrences of alleles typical for North American wapiti (Cervus elaphus canadensis) indicate that the introduced deer originated from English or European deer parks which have had a history of introductions of wapiti in the past. In New Zealand, the superoxide dismutase allele typical for wapiti was found in 1% of red deer, whereas it occurred in 11% of animals in the present study. Polymorphism measured across the nine examined protein systems was 2.0 alleles per locus with an overall heterozygosity of 0.30. The low variations are likely the result of the introduction based on few individuals. However, the outstanding performance of the present population contradicts the existence of any overt impact from this founder effect. The observed large body sizes may not only be due to good environmental conditions, but also due to previous hybridisation with wapiti. Several specimens were heterozygous and one specimen was homozygous for wapiti hemoglobin. © 2011 CSIRO. Source

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