The Stream Microbiome: An Ecosystem’s Health Report Card
Image Credit: mstk east, CC BY 2.0, Image Cropped
Tag Archives: freshwater
Bogs, Beavers and Blood: Freshwater Ecosystems in Film
The freshwater world is full of horror movie potential, and yet most of the time it’s the ocean that is the centrepiece of aquatic horror stories. It’s not entirely unexpected, after all the ocean makes up over 97% of the earth’s water-based surface, and freshwater doesn’t have much to offer in the way of an ‘abyss’.
Read moreMarvels of the African Great Lakes: Studying Cichlids With Dr. Frederic Schedel
Africa has long been romanticized in regards to the natural world. From crocodiles snapping at wildebeest to lions lounging on the plains, the continent is packed with charismatic animals. Often slipping under the radar is the fact that Africa’s freshwater ecosystems are also teeming with stunning wildlife.
Read moreHow Influential is the Platypus in Freshwater Dynamics?
Image Credit: Maria Grist, CC BY-SA 4.0, Image Cropped
Platypus predation has differential effects on aquatic invertebrates in contrasting stream and lake ecosystems (2020) McLachlan-Troup, Scientific Reports, https://doi.org/10.1038/s41598-020-69957-1
The Crux
A trophic cascade occurs when a predator’s effects of its prey goes on to affect ‘lower’ levels of that ecosystem. A great example is the effect that sea otters have on kelp: the sea otters prey extensively on sea urchins, which in turn increases the populations of kelp, which the sea urchins prey on. While this is a result of direct predation by otters, often this can occur through a prey species changing its behaviour to avoid the predators.
Yet most ecosystems are more complex than a simple three-level trophic system. Cascades are therefore more likely to occur when the ecosystem is less complex, or when there are well-defined relationships between species, as a result of a predator having preferred prey species or only a few groups of species making up an ecosystem.
This week’s authors investigated how the platypus (our recently-found-to-be-fluorescent friend) influences the abundance and species richness of invertebrates across both rivers and lakes, and whether it’s capable of affecting an ecosystems algae and sediments as well.
Read moreRebuilding Our Relationship With Urban Rivers With Dr. Cecilia Medupin
Rivers have played a monumental role in determining where people live. Their importance in providing water, transportation and a raft of other ecosystem services has meant that even today most of the world’s largest cities are situated close to a major source of freshwater, from Sydney to Delhi, Quebec to Karachi.
Yet despite their role in our history, urban rivers today are often facing increasing levels of pollution as a result of human activity. As well as often being a huge tourist drawcard, and an ongoing resource for fishers, joggers and portable BBQ toters, freshwater ecosystems carry a disproportionate number of aquatic species, which makes this trend increasingly worrying.
After meeting at last year’s British Ecological Society Annual Meeting, I got in touch with Dr. Cecilia Medupin, a freshwater ecologist at the University of Manchester. Cecilia works to increase peoples understanding of rivers, including the project Our Rivers, Our City. I asked Cecilia abut our connection with rivers, the challenges they face, and how to inspire research and change in urban rivers.
On Fish Dispersal and the Perpetual Evil of the Duck
Image Credit: Norbert Nagel, CC BY-SA 3.0, Image Credit
Woe betide my fishy ancestors, for I am come here today to vent my grievances at a paper so dastardly it has cast a tepid patina of anxiety on a LOT of the structured squabbling my colleagues and I call ‘research’.
Actually, I shouldn’t vent too harshly on the sarcopterygiites, those ancient lobe-finned ancestors of ours and their close cousins the regular fish. Birds, as always, are the main culprit here. An abhorrent series of mutations that messed up a perfectly good reptile.
The Mystery of the Sabertoothed Salmon
Image Credit: Jacob Biewer, Sankey et al., 2015
The charisma of enormous, slashing teeth is undeniable. Despite the fact that there are a myriad of fascinating prehistoric carnivores, the big mammals that the documentaries, big-budget films and kid’s shows seem to come back to are the sabre-toothed carnivores. Massive slashing teeth are actually a trait that has popped up a lot over the course of the Earth’s history, with at least three different groups of cat or cat-like mammal evolving them as a hunting mechanism. As well as a fish.
The 2020 Oikos Write-Up: Ecology in the Anthropocene
My lord Iceland is gorgeous. There could not have been a better setting for the 2020 Nordic Oikos Society’s Annual Meeting. Driving through deserts of snow that ring of the kind of quiet isolation you’d expect from a town in a depressing British murder mystery was a wonderful experience.
As was the conference itself, of course. So let’s recap some of my highlights from this year’s meeting, titled ‘Ecology in the Anthropocene’.
Water-Based Recreation Can Promote Non-Native Introductions
Image Credit: Manfred Antranias Zimmer, Pixabay licence, Image Cropped
Invasion of freshwater ecosystems is promoted by network connectivity to hotspots of human activity (2019) Chapman et al., Global Ecology and Biogeography, https://doi.org/10.1111/geb.13051
The Crux
The spread of invasive species throughout freshwater ecosystems is a topic we’ve looked at before on Ecology for the Masses. In a previous paper breakdown we talked about how recreational is heavily responsible for the presence of non-native fish at a European scale.
Our paper this week takes a more local approach. Can we predict the presence of non-native birds, invertebrates and fish by looking at the presence of human activity, and where that human activity is present?
How Does Our Interpretation Of Urbanisation Affect How Damaging It Is?
Increased urbanisation may have a negative effect on the richness of moth species like this Vine’s Rustic, but it depends on what scale we consider richness (Image Credit: Patrick Clement, CC BY 2.0, Image Cropped)
Urbanization drives cross-taxon declines in abundance and diversity at multiple spatial scales (2019) Piano et al., Global Change Biology, https://doi.org/10.1111/gcb.14934
The Crux
You would think that the effect of building a whole lot of stuff on something’s habitat would have a negative effect on just about anything. But building a whole lot of human stuff (maybe let’s retain a modicum of science-ness and call it urbanisation) hasn’t always been shown to be necessarily bad for species. There are a lot of studies out there which show that urbanisation is can be a negative for biodiversity (which makes sense, since for starters it generally breaks up habitat patches and introduces a whole lot more pollutants). But there are also studies showing that urbanisation can increase biodiversity.
