Want a heads up when we find really cool research and articles about all things fishy? Then you’re in the right place! We’re going to start a monthly roundup of interesting bits and pieces related to marine research and sustainable fishing but also other things we find that have caught our interest that month. So if you need some inspiration, or bedtime reading, we’ll have you covered. Continue reading
Tired of crawling under fences and dodging cow poo, last year I decided to venture out of the farms and into the rainforest to search for Australian Bass. Continue reading
It’s probably no real surprise that both Lac and I do a fair bit of fishing (some say too much). In the past we’ve documented what we’ve been catching on Instagram, but are often left with pictures from our fishing trips which end up clogging our hard drives. So this year we have created a “Fishing Journal” page on the blog to share some thoughts and pictures from our fishing adventures. Continue reading
This guest post by Laura Lopez, a PhD candidate from the University of Wollongong who is looking at the behavioural interactions between the introduced Eastern Mosquito fish and native fauna. Below is a summary of her awesome work on glass shrimp. Laura is also assessing the impact of Eastern Mosquito fish on Australian Bass so hopefully we can get an update on this work later in the year!
Eat or be eaten: invasive fish forces shrimp to make tough life decisions
by Laura Lopez
Predation is often presented as a rather simple, albeit dramatic sequence. We might think of a cheetah chasing down a lone gazelle, or the aerial aerobics of a great white shark ambushing a rather unfortunate sea lion. While it’s true that the immediate impact of predation is one less prey animal and one satisfied predator, there is a whole other side to this interaction that we can’t easily see.
In reality, predation is actually a complex interaction, the outcome of which depends on predator behaviour and motivation, prey behaviour and the environment. Fear of a predator itself has a powerful effect on prey animals and can be both a blessing and a curse. For example, while hanging out on the beach might help a sea lion avoid a shark attack, it also prevents it from feeding. Therefore, while avoiding exposure to predators might help prevent being eaten (known as a consumptive effect) it also leads to a loss of fitness in the long term (known as a non-consumptive effect).
For prey to make the most of this trade-off, they need to be able to tell when it’s a good time to go out, or a good time to stay home. A further complication is the fact that predator density and therefore behaviour can vary, as can the time of day. I’ve been researching this conundrum by observing how different densities of the invasive freshwater Eastern Mosquito fish, Gambusia holbrooki, predate upon and alter the behaviour of a native glass shrimp, Paratya australis, during the day and at night. The Eastern Mosquito fish is a tiny but devastating introduced species which has been very successful in Australia. However, we don’t know much about how it’s interacts with native species as a predator.
Female (berried) glass shrimp. Elastomer tag injected into the tail to allow individuals to be identified.
I was reading one of the bigger ecology blogs that I find myself returning to fairly regularly and they posted a review of their blog year, mostly for themselves to reference. I found it interesting so went to have a look at our own blog and social media stats. I thought I’d post a fish thinkers summary mainly as a record for myself but also on the odd chance anyone else is vaguely interested (its also a sneaky way to kick off a year in which I plan to post on here more regularly). Continue reading