Abstract: A series of automatic time-lapse cameras installed along the southwestern side of Tasiapik Valley, near the village of Umiujaq, Nunavik (northern Québec) documented several departure modes and types of snow involved in snow avalanches during winter 2017–2018. These included cornice–avalanche dynamics, slab and loose snow avalanches, and clean and dirty snow avalanches. At the top of the selected slope, a camera monitored the development of a snow cornice beginning in November 2017, detecting multiple cornice failures over the winter and spring. The track and deposition area of the runout paths were monitored from two cameras downslope, revealing the concomitance of snow–cornice fall and snow avalanche triggering. Snow avalanche activity remained relatively infrequent until the end of May 2018. Spring snow avalanche activity is characterized by wet and dirty snow avalanches carrying debris to the foot of the slope and by runout zones located near the road along the slope.

Abstract: Sharing the same wintering grounds by avian populations breeding in various areas may synchronize fluctuations in vital rates, which could increase the risk of extinction. Here, by combining multi-colony tracking with long-term capture-recapture data, we studied the winter distribution and annual survival of the most numerous Arctic seabird, the little auk Alle alle. We assessed whether little auks from different breeding populations in Svalbard and Franz Josef Land use the same wintering grounds and if this leads to synchronized survival. Our results indicate that birds from the Svalbard colonies shared similar wintering grounds, although differences existed in the proportion of birds from each colony using the different areas. Little auks from Franz Josef Land generally spent the winter in a separate area, but some individuals wintered in the Iceland Sea with Svalbard populations. Survival data from 3 Svalbard colonies collected in 2005-2018 indicated that sharing wintering grounds did not synchronize little auk annual survival rates. However, it is clear that the Iceland Sea is an important wintering area for little auks, and environmental changes in this area could have widespread impacts on many populations.

Abstract: A broad range of climatic and biogeographical conditions are represented in the French Overseas Territories, from sub-polar to equatorial, resulting in a high diversity of endemic species. We mobilized data from herbaria, floras, checklists, literature, the expertise of botanists and plant ecologists to compile the most complete dataset on endemic vascular plants and bryophytes in the 15 French Overseas Territories. To date, 3748 spermatophytes (seed plants), 244 pteridophytes (ferns and lycophytes) and 448 bryophytes are strictly endemic to the overseas territories. New Caledonia, French Polynesia and Réunion harbour the highest numbers of strictly endemic species, yet French Guiana and the French Antilles harbour high numbers of regional endemic species due to their proximity with other territories. The endemic flora of these territories is highly threatened. In particular, 51% of strictly endemic spermatophytes are threatened and many species at risk belong to Rubiaceae and Orchidaceae families. Around 82% and 69% of strict and regional endemic spermatophytes and pteridophytes are found in the Paris herbaria. Only 34% of endemic bryophytes have their label information fully databased so that their total number in Paris herbaria is not known. Databasing the remaining specimens in the collection will greatly enhance future research and conservation projects. To facilitate the use of the information we compiled, we provide a publicly searchable dataset of the checklist. This study not only provides a picture of the flora of French overseas territories; it also identifies gaps in knowledge on which future research efforts in systematics, ecology and conservation could focus.

Abstract: In altricial species, parents brood their chicks constantly before leaving them unattended sometimes for extended periods when they become thermally independent. During this second phase, there is sometimes important inter-individual differences in parental attendance and the fitness costs and benefits of parental strategies have previously been extensively investigated. However, the impact of parental presence on offspring behaviors and stress physiology has been overlooked. Here, we examined the influence of parental presence on offspring hormonal and behavioral stress sensitivities in snow petrel chicks. We demonstrated for the first time in a wild bird species that attended chicks had lower stress-induced corticosterone levels and a lower probability to show defensive behavior compared to the alone chicks. This reduced stress sensitivity is certainly explained by the well-known link between corticosterone and nutritional status, and by the recent delivery of meals to the attended chicks and the improvement of their nutritional status. It may also be explained by the parental protection against predators or inclement weather, or/and by the psychosocial comfort of parental presence for the offspring. Overall, these results suggest that the presence of a parent in the nest reduces offspring stress sensitivity in wild birds. Further studies would now be required to disentangle the impact of nutritional status and parental presence on stress sensitivity and to better understand the potential impact of parental presence and circulating corticosterone levels on growth and cognitive development in wild birds.