Podcast Episode: Dr Daryl McPhee

Academic and author Daryl McPhee kindly answered a bunch of my questions in the latest episode of the podcast! Daryl’s has a wide range of interests and spends a LOT of contact time with Moreton Bay, so his book, Environmental History and Ecology of Moreton Bay is a goldmine for the rest of us!

Here’s the episode:

Daryl has a Facebook page for the book, where he posts news, events, and articles of interest.

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Loving them to death. Dolphin feeding at Amity

Had to post a wee bit on this, as my teenage niece loves to drive me nuts reporting another of her acquaintances on Snapchat has posted selfies feeding the dolphins at Amity. It’s happened a lot this summer 😬

We all love dolphins. Seeing them up close is one of life’s great pleasures, and it’s probably natural for us to want to interact with them in some way. In the absence of owning a set of our own fins or flukes, we tend to do the only thing we can think of that will bring them closer – give them fish.

Unfortunately, unregulated feeding of dolphins is a really bad thing for them. It changes their behaviour – they spend more time near humans, where they can pick up diseases they wouldn’t normally come in contact with. They lose their fear of boats, so they’re at higher risk of boat strikes. Mothers spend less time looking after their calves, so calf mortality is higher. They can also become aggressive to humans!

Feeding dolphins at Amity Point brings them into proximity with fishers and swimmers – and some of our local dolphins have already suffered for it. Also, it’s illegal, and you can cop a pretty nasty fine for it.

Without regulation, there’s no limit to the amount of time dolphins will spend “begging” for food from humans. Regulations reduce or even remove the risks to dolphins from provisioning. Licences are granted in places like Monkey Mia or Tangalooma because they’ve recognised the problems with provisioning, and stick to strict limits (for number of fish given, AND number of humans doing the feeding) so the dolphins know they need to get back out to the wild and do their wild, natural thing. They will also see individual dolphins over many visits, and be able to recognise if their behaviour is changing, and adjust the limits accordingly. If you just have to interact, choose to do it where it’s not hurting the animal you love! Choose a licensed operator.

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Range shifts: a new crew of critters?

All organisms evolve in the hope of first surviving in the conditions around them, and if they’re lucky, they continue to evolve to thrive in those conditions.

This happens over many, many generations of organismal life, which means the speed of evolution is different for each species. For example, the time it takes bacteria to evolve is very short, because they are so numerous and reproduce quickly, so beneficial mutations can take hold in the population much faster. Species that are long-lived, and have few offspring, however, can’t cope with rapid change to their environment. There isn’t enough time for them to have the generations of offspring necessary to evolve the new traits the species needs.

For immobile species, like plants or corals, this is bad news. For mobile organisms, like fish, they can the only way the species can survive is to move to where conditions are better, if they can.

If you’re a marine fish, you’ve evolved to survive within in certain ranges of temperature, salinity, oxygen levels, and the presence of predators and prey. If any of these change, you might look next-door to find your sweet spot, and “move in” if you can. Because ocean temperatures are warming across the globe, that means species living toward the equator will retreat toward the poles.

This is what’s known as “range shift” – and as Darryl told us, this could see changes to the type of fish we see and catch in Moreton Bay. It is likely we’ll catch fewer luderick, for example, and see more threadfin salmon or barrimundi.

It doesn’t sound too bad, does it? Moreton Bay having the same temperature as (used to!) be so beneficial for the Great Barrier Reef? Maybe sometime soon Moreton Bay might even become the new GBR? Don’t count on it, especially not within our lifetimes.

Range shifts are happening all over the world, on land and in the oceans, due to climate change. It’s creating “winner” and “loser” situations, both for species, and for us. Don’t forget, humans are a species too, and though we’re numerous, we’re also long-lived and comparatively we don’t reproduce anywhere near quickly enough to evolve to match climate conditions! So as a species, we’ll be dealing with all the same changes a fish does – changed conditions, increased or decreased availability of food, previously supportive habitats that are increasingly hospitable to our lives.

Scientists are pretty keen to monitor changes to our marine ecosystems, and have suggested fisheries and museums databases should be co-opted for the purpose. You can help too! An organisation called Redmap has sprung up for exactly this purpose. Redmap (Range Extension Database and Mapping project) invites the community to submit sightings of species that are uncommon to an area of the coast. If all our fishers and bayside residents got on the case, we could get a really robust picture of the changes taking place in Moreton Bay. (NB: Redmap’s Facebook page will often post unusual sightings, so give them a follow!)

Find out more about Daryl, or contact him, via his Bond University faculty page.