Are avian predators effective biological control agents for rodent pest management in agricultural systems?

Worldwide rodent pests are of significant economic and health importance. Controlling rodent pests will, therefore, not only benefit food security but also human and animal health. While rodent pests are most often chemically controlled, there is increased interest in biological control through avian predation. A rich body of research has addressed the impact of avian predators on wild rodent populations, but little is known about the effectiveness of avian predators as biological control agents of rodent pests in agricultural systems. In this study, we systematically reviewed research that investigated different aspects of avian predation on rodent pest populations in order to increase our understanding of the impact and effectiveness of avian predation on rodent pests. Several avian predators (Tyto alba, Elanus axillaris Falco tinnunculus, F. cenchroides, Bubo bengalensis, Buteo rufinus) were commonly cited in the biological control of rodents; however, barn owls (T. alba) are the most cited species (86% of studies). We found some support that the use of avian predators produced positive, measurable effects where increased presence of avian predators tended to lower rodent pest numbers, resulting in lower crop damage. However, our review highlighted several shortcomings related to research on avian predation of rodent pests. First, research concerning rodent pest control through avian predation was limited (1.86 articles per year). Secondly, we found that studies lack statistical rigor to detect and measure change in rodent pest species abundance. Finally, the majority of studies were short term and therefore not able to evaluate long term sustainable rodent pest population suppression. We suggest that current shortcomings could be adequately addressed with control-treatment studies that quantitatively investigate the effects of avian predation on rodent pest populations and agricultural impact. Such research could help develop recommendations regarding the use of avian predators in rodent pest management

Arthroscopic autologous chondrocyte implantation for the treatment of a chondral defect in the tibial plateau of the knee

The matrix-induced autologous chondrocyte implantation (MACI; Verigen, Leverk\ufcsen, Germany) is a tissue engineering technique for the treatment of deep chondral lesions. Cultured chondrocytes are seeded on a collagen membrane that can be implanted into the defect using exclusively fibrin glue. These features imply some surgical advantages with respect to the traditional ACI technique, such as the possibility of performing the procedure in articular sites, in which putting stitches for the periosteal patch is impossible. We report on the arthroscopic MACI technique for the treatment of a chondral defect of the knee. A 25-year-old man suffered persistent pain at the left knee after a violent direct trauma. Magnetic resonance imaging (MRI) and arthroscopic examination at the time of cartilage biopsy revealed a 2-cm2 chondral lesion in the posterior portion of the lateral tibial plateau. The implantation procedure was performed through traditional arthroscopic portals, and the seeded membrane was fixed with fibrin glue, excluding water flow temporarily. Implant stability was verified intraoperatively, and filling of the defect was shown 12 months after surgery by MRI, which showed a hyaline-like cartilage signal. In this specific case, the arthroscopic approach allowed to achieve an optimal view of the lesion, without sacrificing any tendinous or ligamentous structure of the knee

Footprints of climate change in the Arctic marine ecosystem

In this article, we review evidence of how climate change has already resulted in clearly discernable changes in marine Arctic ecosystems. After defining the term 'footprint' and evaluating the availability of reliable baseline information we review the published literature to synthesize the footprints of climate change impacts in marine Arctic ecosystems reported as of mid-2009. We found a total of 51 reports of documented changes in Arctic marine biota in response to climate change. Among the responses evaluated were range shifts and changes in abundance, growth/condition, behaviour/phenology and community/regime shifts. Most reports concerned marine mammals, particularly polar bears, and fish. The number of well-documented changes in planktonic and benthic systems was surprisingly low. Evident losses of endemic species in the Arctic Ocean, and in ice algae production and associated community remained difficult to evaluate due to the lack of quantitative reports of its abundance and distribution. Very few footprints of climate change were reported in the literature from regions such as the wide Siberian shelf and the central Arctic Ocean due to the limited research effort made in these ecosystems. Despite the alarming nature of warming and its strong potential effects in the Arctic Ocean the research effort evaluating the impacts of climate change in this region is rather limited. © 2010 Blackwell Publishing Ltd.This research is a contribution to the Arctic Tipping Points project (http://www.eu-atp.org) funded by FP7 of the European Union (contract 226248) and ARCTOS, a north-Norwegian network that emphasises interdisciplinary approaches to addressing large-scale questions in marine Arctic oceanography (http://www.arctosresearch.net).Peer Reviewe