If you are in Jervis Bay and see someone knee deep surrounded by rays or alternatively sitting staring at rays for hours on end then chances are you are looking at the “mother of rays” otherwise known as Joni – the driving force behind the Stingray Diaries. She’s studying smooth stingrays throughout the Jervis Bay Marine park, in conjunction with Fisheries NSW and gives us a rundown on her research in her guest blog below…
Top shelf bottom feeders
Learning to swim by getting thrown off the end of a busy public wharf on the Hawkesbury River in nothing but a pair of hot pink floaties… Living in a swimsuit and covered in sand every single day of the year… Chucking tantrums when told to come inside after playing on the beach all day because it was dark… At the age of 4, saying with great certainty, “Mum, when I grow up I’m going to be a Marine Biologist.” Continue reading →
Damien Vella is Senior Horticulturist at the Botanic Gardens and does a great job of sharing natural history moments he encounters throughout his life on his instagram account. He has a particular skill for taking events from the backyard and telling a story that weaves in the underlying ecology in a fascinating way. He also shares one of my deep interests-that is creating habitat in backyards (Even better that it is the aquatic type).
Caroline (from over at CCU Shark Research Team) stopped by the Fish Thinkers blog to give us a run down on where her research is headed and a sneak peak into the world of grad student shark research in the United States. Continue reading →
We as consumers, particularly in western countries, are pretty boring when it comes to our seafood. Given the diversity of fish in our oceans this seems pretty strange. It’s like our taste buds are only fond of a handful of species such as tuna, cod, salmon, flake etc. But our obsession for these fish (majority of which are apex predators), has resulted in many of their stocks becoming overfished and deterioration of the ecosystems in which they live in. So it’s time we started mixing things up in terms of what seafood we catch, order, buy and cook!! This leads me to today’s guest post by Lauren Yates of Ponytail Journal. Lauren runs a super successfully blog covering all things from fashion, food and travel. When it comes to cooking, Lauren is a huge advocate of using sustainable seafood, regularly encouraging her followers to steer clear of the ‘trendy’ species that are overexploited and explore more sustainable options. Read her post below on why salmon can’t be on the menu anymore… 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
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.