Image Credit: Dennis Jarvis, CC BY-SA 2.0, Image Cropped
Integrating dispersal along freshwater systems in species distribution models (2020) Perrin et. al., Diversity & Distributions, https://doi.org/10.1111/ddi.13112
Trying to figure out where a species can comfortably live is one thing, but figuring out which habitats they can actually access is another. I like to think most marsupials would do quite well in South America or Africa, but the fact is that they’re not dispersing across the Atlantic or Pacific anytime soon. However a Species Distribution Model (a statistical model that can be used to predict the likelihood of a species being found somewhere) often requires a more nuanced approach than “big ocean separating these two habitats”.
To integrate a species’ ability to actually access an area into a Species Distributions Model (SDM), we often use the concept of connectivity. Often, this means simply measuring the distance between two populations. But sometimes a species ability to disperse might not reflect something as simple as how far it needs to go. A perfectly good habitat might be only 100 metres away, but cut off by a raging great cliff. Or a road.
In this study, we wanted to see whether we could relate connectivity parameters used in an SDM to the actual ability of the species to disperse.
Birds like this American tree sparrow are declining rapidly, shows a study which looks at huge declines in North American bird populations (Image Credit: Ryan Hodnett, CC BY-SA 4.0, Image Cropped)
Decline of the North American avifauna (2019) Rosenberg et al., Science, DOI: 10.1126/science.aaw1313
When we talk about species loss, we generally focus on extinctions. Too often, when we start to rally around a species, it’s because there are a particularly low number of that species left. In many cases, they’ve often crossed a threshold, from which it’s impossible to pull them back from the brink of extinction.
Often this draws attention away from non-threatened species. Often that’s fine – they’re non-threatened right? But downward population trajectories in these species can still damage ecosystems by lessening the impact of their ecological function, lead to local (if not total) extinctions, and of course, leading them to eventually be threatened.
This week’s authors wanted to look at bird population declines in America, but from the perspective of total abundance, as opposed to a more species-specific view.
Image Credit: rumpleteaser, CC BY 2.0, Image Cropped
2019 was a year in which many changes that our planet is experiencing came to the fore, capped off in December by the Australian bushfires, a phenomenon that scientists predicted would start to occur with increasing intensity at the beginning of last decade. With all the change that our planet is currently undergoing, it’s always worth noting that the discipline of ecology itself has changed as well.
Over 2019 we got to sit down and talk to some pretty exciting people. And whether they were at the forefront of genomics, the science-policy interface, or the wave of inclusivity currently sweeping ecology, they all had some great comments on how ecology has changed over the last few decades.
Image Credit: GBIF, CC BY 4.0, Image Cropped
When I was a child, I’d often study books of Australian birds and mammals, rifling through the pages to see which species lived nearby. My source of information were the maps printed next to photos of the species, distribution maps showing the extent of the species range. These days, many of these species ranges are declining. Or at least, many ecologists believe they are. One of the problems with knowing exactly where species exist or how they are faring is a lack of data. The more data we have, the more precise an idea we get of the future of the species. Some data is difficult to collect, but yet more data has been collected, and is simply inaccessible.
At the Living Norway seminar earlier this month I sat down with Tim Robertson, Head of Informatics and the Global Biodiversity Information Facility. GBIF is an international network that works to solve this data problem worldwide, both by making collected data accessible and by helping everyday people to collect scientific data. I spoke with Tim about the journey from a species observation to a species distribution map, the role of GBIF, and the future of data collection.