Snowmelt and laying date impact the parental care strategy of a high-Arctic shorebird.

Why parental care strategies can vary from uniparental to biparental care across taxa remains unclear, likely because various sets of ecological conditions are at-play. Here we tested ten possible hypotheses to decipher the direct and indirect impacts of critical factors likely to influence the parental care strategy during incubation in Sanderlings (Calidris alba), one of the few species that uses both types of care during that critical time of the breeding cycle. We examined three ecological factors (timing of local snowmelt, regional temperatures, and the North Atlantic Oscillation experienced just before breeding), one trophic factor (predation pressure), and two social factors (relative abundance of Sanderlings and their laying dates).

Extended incubation recesses increase before nest abandonment in a high-arctic shorebird.

Parents can abandon their current clutch when reaching a physiological threshold to prioritise their survival and future breeding in the trade-off against current reproduction. Incubation is metabolically costly, and regular recesses are necessary to replenish energy reserves. Thus, an increase in the duration of these foraging trips may signal diminishing reserves and perhaps impending abandonment.

Extended incubation recesses in sanderlings are impacted by temperature and body condition.

Complex incubation strategies have evolved to solve the trade-off between parent survival and care for their eggs with often brief departures (recesses) that maximize egg survival, and infrequent extended recesses maximizing adult condition. Here we examined incubation behaviour of sanderlings (), a species that exhibits both biparental and uniparental incubation behaviour. During 11 breeding seasons in Greenland, we have quantified incubation variability with thermologgers placed in nests.

Sex-, age-, and time-specific visual communication in brown bears.

Intraspecific communication in mammals is well-documented but generally restricted to chemical and acoustic signaling. However, other overlooked channels, such as visual signaling, may be used to communicate among conspecifics. Here, by using experimental manipulations together with camera traps on 13 brown bear () rubbing trees in the Cantabrian Mountains (northwestern Spain), we document detailed temporal patterns and behavioral aspects of a recently discovered novel communication channel for this species, visual signaling through the trunk debarking of focal trees.