Time filter

Source Type

Puerto Montt, Chile

Correa-Araneda F.,Fisheries Development Institute | Correa-Araneda F.,Catholic University of Temuco | De Rios P.L.,Catholic University of Temuco | Habit E.,University of Concepcion
Revista Chilena de Historia Natural

Background: Brachygalaxias bullocki (Regan, 1908) is a small-sized freshwater fish species (41 to 46 mm) and endemic to Chile. Its biology has still various knowledge gaps, and its distribution range has been reduced in the last decade due to human intervention. Findings: In this article, for the first time, its presence in forested wetlands of Chile (38° 52 ′ to 39° 02′ S) is documented. The presence of this species in these ecosystems is restricted to wetlands with permanent water regime and depths ranging from 15.7 to 83.5 cm. Conclusions: The physicochemical habitat conditions show important seasonal variations, suggesting that B. bullocki is resistant to a wide range of temperatures, as well as different levels of dissolved oxygen and conductivity. © 2014 Correa-Araneda et al.; licensee Springer. Source

Correa-Araneda F.,Fisheries Development Institute | Correa-Araneda F.,University of Concepcion | Boyero L.,CSIC - Donana Biological Station | Boyero L.,James Cook University | And 7 more authors.
Aquatic Sciences

Joint effects of climate warming and other stressors are potentially complex and difficult to predict. In stream ecosystems, exotic riparian species have the potential to alter leaf-shredding detritivorous invertebrate assemblages and leaf litter breakdown due to differences in the quality of litter inputs. This is the case for Eucalyptus plantations, which are widespread, occurring along riparian corridors of streams around the world. We hypothesised that the presence of Eucalyptus globulus (Labill.) litter (1) impairs detritivore fitness both directly (i.e., through leaf consumption) and indirectly (i.e., through leaf leachates in the water) and (2) impairs litter breakdown, (3) with stronger effects at higher temperatures. We tested these hypotheses in microcosm experiments with two detritivore species from two locations: the stonefly Diamphipnosis samali (Illies, 1960) in Chile and the caddisfly Calamoceras marsupus (Brauer 1865) in Spain. Eucalyptus leaves affected detritivore growth mainly by direct consumption, while the presence of both Eucalyptus leaves and leachates inhibited the breakdown of native litter. When both litter types were available, breakdown of Eucalyptus leaves was enhanced, possibly as a means of compensatory feeding. Increased temperature exacerbated the negative effect of Eucalyptus on native litter breakdown, possibly because it reduced detritivore survival. Our results add to the mounting evidence that joint effects of multiple stressors can be non-additive, and suggest that the sole presence of Eucalyptus leaves and leachates in the water may impact stream communities and ecosystem functions even if native litter is available, with further negative effects to be expected under a warmer climate. © 2014, Springer Basel. Source

Gomez-Lobo A.,University of Chile | Pena-Torres J.,Alberto Hurtado University | Barria P.,Fisheries Development Institute
Environmental and Resource Economics

In 2001 an individual (operationally transferable) quota system was introduced for all the most important industrial fisheries in Chile. This system was put in place after years of declining stocks and over investment. In this paper we describe this reform and estimate related allocative efficiency benefits for the most important industrial fishery in the country, the southern pelagic fishery. Benefits were estimated using a bioeconomic model estimated using data for the 1985-2004 period. The estimated model was then used to generate simulated scenarios of the evolution of this fishery in a 20 year horizon with and without the ITQ system in place. The benefits of the reform can then be estimated by comparing the fishery's costs in the scenarios with and without ITQs. This approach allows benefits to be estimated using more realistic counterfactual scenarios than just comparing the fishery before and after the reform. Estimated discounted net benefits reach US $166 million in the period 2001-2020. Fleet size fell from 149 active boats in 2000 to 57 in 2004 as a direct consequence of the reform. Among the interesting features of the Chilean experience is the way the political economy of the reform was facilitated by the prior introduction of de facto individual quotas within the framework of fishery experimental activities. When the authorities closed the southern pelagic fishery because of biological problems between 1997 and 2000, they organized 'experimental' fishing expeditions in which participant boats were given the right to fish a certain amount of resources per expedition. This pseudo quota system allowed fishermen to experience directly the benefits of individual quotas and that was instrumental to the political agreement leading to the reform. It is important to note that the Chilean southern industrial pelagic fishery has average catches of over 1.4 million tons a year, making it one of the largest fisheries in the world to be regulated by individual quotas. © 2010 Springer Science+Business Media B.V. Source

Correa-Araneda F.,Fisheries Development Institute | Correa-Araneda F.,University of Concepcion | Correa-Araneda F.,Catholic University of Temuco | Diaz M.E.,University of Concepcion | And 4 more authors.

The macroinvertebrate community of Mediterranean forested wetlands (FW) in Southern Chile was studied to determine their temporary distribution patterns in relation to changes in the hydroperiod. A total of 540 samples were collected over a period of one year using three complementary techniques. The results indicated a total of 80 taxa dominated by Chironomidae, Oligochaeta and Hyallela araucana. These communities presented significant differences among wetlands with different water regimes (ANOSIM Global R 0.45, p = 0.001) and between different seasons (p < 0.05). The seasonal differences were clearer in temporary wetlands, which were directly related to depth changes (r > 0.64, p < 0.05). These differences were primarily due to the following taxa: Asellidae, Chironomidae, Hyallela araucana, Littoridina sp. and Oligochaeta. An important number of exclusive and rare taxa were also determined according to the different regimes. The clear influence of the hydroperiod on the community patterns of the benthic macroinvertebrates (BMI) and the importance of conserving these ecosystems as reservoirs of a unique diversity that distinguish these types of wetlands are discussed. © Asociación Ibérica de Limnología, Madrid. Spain. Source

Discover hidden collaborations