Chlamydia pecorum prevalence in South Australian koala (Phascolarctos cinereus) populations: identification and modelling of a population free from infection

Chlamydia pecorum is an established and prevalent infection that produces severe clinical disease in many koala populations, contributing to dramatic population declines. In wild South Australian koala populations, C. pecorum occurrence and distribution is unknown. Here, C. pecorum-specific real-time quantitative PCR (qPCR) was applied to ocular and urogenital swabs from targeted surveys of wild koalas from the mainland Mount Lofty Ranges (MLR) (n = 75) and Kangaroo Island (KI) (n = 170) populations. Historical data from 13,081 KI koalas (1997-2018) provided additional evidence for assessing the absence of C. pecorum infection. In the MLR population, 46.7% (CI: 35.1-58.6%) of koalas were C. pecorum positive by qPCR but only 4% had grade 3 clinical disease. MLR koala fertility was significantly reduced by C. pecorum infection; all reproductively active females (n = 16) were C. pecorum negative, whereas 85.2% of inactive females (n = 23) were positive (P < 0.001). KI koalas were C. pecorum negative and the population was demonstrated to be free of C. pecorum infection with 95% confidence. C. pecorum is a real threat for the sustainability of the koala and KI is possibly the last isolated, large C. pecorum-free population remaining in Australia. These koalas could provide a safeguard against this serious disease threat to an iconic Australian species.Jessica Fabijan, Charles Caraguel, Martina Jelocnik, Adam Polkinghorne, Wayne S.J. Boardman, Elisa Nishimoto, Greg Johnsson, Robyn Molsher, Lucy Woolford, Peter Timms, Greg Simmons, Farhid Hemmatzadeh, Darren J. Trott, Natasha Speigh

Navigating infection risk during oviposition and cannibalistic foraging in a holometabolous insect

Deciding where to eat and raise offspring carries important fitness consequences for all animals, especially if foraging, feeding and reproduction increase pathogen exposure. In insects with complete metamorphosis, foraging mainly occurs during the larval stage, while oviposition decisions are made by adult females. Selection for infection avoidance behaviours may therefore be developmentally uncoupled. Using a combination of experimental infections and behavioral choice assays, we tested if Drosophila melanogaster fruit flies avoid infectious environments at distinct developmental stages. When given conspecific fly carcasses as a food source, larvae did not discriminate between carcasses that were clean or infected with the pathogenic Drosophila C Virus (DCV), even though cannibalism was a viable route of DCV transmission. When laying eggs, DCV-infected females did not discriminate between infectious and non-infectious carcasses. Healthy mothers however, laid more eggs near a clean rather than an infectious carcass. Avoidance during oviposition changed over time: after an initial oviposition period, healthy mothers stopped avoiding infectious carcasses. We attribute this to a trade-off between infection risk and reproduction. Laying eggs near potentially infectious carcasses was always preferred to sites containing only fly food. Our findings suggest infection avoidance contributes to how mothers provision their offspring and underline the need to consider infection avoidance behaviors at multiple life-stages

Comparison of the thickness of the calvarium between young grey (Halichoerus grypus) and harp (Pagophilus groenlandicus) seals

Title and Abstract in English and French. French title: Comparaison de l'épaisseur de la calotte crânienne entre les jeunes phoques gris (Halichoerus grypus) et les jeunes phoques du Groenland (Pagophilus groenlandicus).Young harp seals (Pagophilus groenlandicus) have traditionally been hunted along the Canadian Atlantic coast, and regulations are now in place to ensure that this hunt meets adequate standards of animal welfare. These young seals are killed by a blow to the head from a hakapik or a club or by a bullet to the head. A hunt for young grey seals (Halichoerus grypus), using similar methods, occurs intermittently on a smaller scale around the Canadian Maritime provinces. However, field observations suggest that the skull of young grey seals is substantially thicker than that of young harp seals. The results of this study confirm these field observations and suggest the need for further research when adapting the current hunting methods for young harp seals to grey seals. = Les jeunes phoques du Groenland (Pagophilus groenlandicus) ont historiquement été chassés sur la côte atlantique du Canada, et des règlements sont maintenant en place pour assurer que cette chasse se déroule selon des standards de bien-être animal adéquats. Ces jeunes phoques sont tués par un coup de hakapik ou de gourdin sur la tête ou par une balle de carabine dans la tête. Une chasse à plus petite échelle pour les jeunes phoques gris (Halichoerus grypus), utilisant des méthodes similaires, se fait de manière intermittente dans les provinces maritimes. Cependant, les observations sur le terrain suggèrent que le crâne des jeunes phoques gris est nettement plus épais que celui des phoques du Groenland. Les résultats de cette étude confirment ces observations et suggèrent un besoin de recherche pour adapter les méthodes de chasse courantes pour les jeunes phoques du Groenland aux jeunes phoques gris.Charles Caraguel, Pierre-Yves Daoust, and Fiep de Bi

Appui au réseau Alpages sentinelles dans les Parcs nationaux alpins

Ce rapport présente la genèse et les finalités du réseau Alpages sentinelles qui vise à comprendre et anticiper l'impact des aléas climatiques sur les alpages par l'acquisition de connaissances et de références techniques sur les processus reliant climat, milieux (vus en termes de biodiversité et de ressource pastorale), pratiques pastorales et systèmes d'élevage des exploitations utilisatrices des alpages. L'autre finalité est une ambition de recherche partenariale visant à faire fonctionner un dispositif d'observations partagées entre des collectifs associant éleveurs, bergers, techniciens agricoles, pastoralistes, chercheurs et gestionnaires d'espaces protégés. Fin 2011, le réseau compte 25 couples alpages x exploitations dans les parcs nationaux des Ecrins et de la Vanoise. Les principales démarches méthodologiques et protocoles d'observation sont présentés, ainsi que des premiers résultats issus des suivis. Les valorisations issues de ce dispositif sont mentionnées