Image Credit: Jasja Dekker, CC BY-SA 2.0, Image Rotated and Cropped
State dependence of arousal from torpor in brown long-eared bats (Plecotus auritus) (2022) Soras et al., Journal of Comparative Physiology B, https://doi.org/10.1007/s00360-022-01451-8
When an animal is facing a lack of prey, or the weather is making it too difficult for them to keep on keeping on, they might choose to enter a state known as torpor. This occurs when the animal lowers its metabolic rate drastically, sometimes to less that 1% of its normal rate. It’s not a perfect solution though, as the costs of torpor include sleep deprivation and memory loss. Nevertheless, it’s a go-to for many small mammals, since they’re warmed up much more quickly than larger ones, and can snap out of torpor when they need to.
It might sound like this is cold-weather behaviour, but it can also occur in summer. Especially if you’re a nocturnal mammal living in part of the world where nights can be very short, or even non-existent, like Scandinavia. Long days means reduced hunting times, so using torpor might be necessary to get through summers as well as winters! This week’s researchers wanted to better understand how small bats survive in northern Norway by looking at how and when they awake from torpor.
It’s Fat Bear Week!
An annual (as chosen by the fans) competition to find the bear who had the most summer gains in preparation for their winter downtime. As they won’t be coming out to forage during the winter months, the bears need to spend the summer months not only regaining that which they lost the previous winter but also shoring up their reserves for the coming winter. This means finding foods that are rich (fatty) and plentiful – salmon happen to tick both of these boxes and are one of the highly sought after snacks over the summer time.
Read More: Fat Bear Week
Check out the before and after shots of these cuddly teddies below!
Fat Bear Week 2021: Before-and-After Pictures of the Contenders
Although this year’s winner has already been voted for (all hail Otis) there is always next year to pick out your bracket and vote for the bear that you think deserves the honours of being the Fat Bear Champion.
Tanya Strydom is a PhD student at the Université de Montréal, mostly focusing on how we can use machine learning and artificial intelligence in ecology. Current research interests include (but are not limited to) predicting ecological networks, the role species traits and scale in ecological networks, general computer (and maths) geekiness, and a (seemingly) ever growing list of side projects. Tweets (sometimes related to actual science) can be found @TanyaS_08.
Male echidna must stay on the move to find females before other males do (Image Credit: JKMelville, CC BY-SA 3.0, Image Cropped)
Energetics meets sexual conflict: The phenology of hibernation in Tasmanian echidnas (2019) Nicol et al., Functional Ecology, https://doi.org/10.1111/1365-2435.13447
Seasonality (i.e. the change in season throughout the course of the year) has huge impacts on the lives of animals that live in temperate habitats. The change in season is associated with changes in food availability, and as such some animals hibernate through the tough winter months and wait until the food and warmer weather comes back. Another aspect of an animal’s life impacted by seasonality is the breeding season, as animals living in temperate habitats must time their breeding around the winter months, while animals in tropical habitats can breed year-round.
Within a single species the timing of hibernation may be affected by the different energetic and reproductive needs of the different sexes. Females may start hibernating later than males because they have to store more energy for their pregnancy and lactation, while males may emerge from hibernation earlier than females to establish territories and increase their chance of mating. Tasmanian echidnas (Tachyglossus aculeatus) exhibit markedly different hibernation patterns among the sexes, and the authors of today’s study wanted to know if these differences are due to where they live or whether they are inherent to the species itself.