The second of GeelongPort’s 2023 citizen science trips to Avalon Coastal Reserve was a chance to survey the saltmarsh during the winter season and reflect on seasonal changes to this dynamic ecosystem.
Right off the bus there were some obvious differences in environmental conditions, with the saltponds underwater due to recent rains. To detect any seasonal differences to the biodiversity, our intrepid citizen scientists undertook the same bug and bird surveys we conducted in March across our control (saltpond), restored for 8+ years and restored for 50+ years sites.
Waders, raptors, and wrens – oh my
In the recently restored saltmarsh sites, one of our teams began to wonder if anything more than a handful of gulls would fly over during the 20-minute survey, despite seeing plenty of other birds around outside of our 2-hectare survey area. It was a good chance to talk about why repetition (e.g., surveying multiple areas) is important when trying to count mobile species like waterbirds – and why ongoing monitoring is vital to our understanding of how changes to vegetation (e.g., through restoration efforts) is having an impact.
In the end both survey areas were visited by quite a few birds – at least ten confirmed species (though the citizen scientists were quickly introduced to the concept of “little brown birds” in birdwatching!). Silver gulls, royal spoonbills and straw-necked ibis flew overhead in small flocks, and a nankeen kestrel did some surveying of its own. We also saw what looked to be several red-necked stints. These tiny migratory birds usually leave Australia by mid-April to head up to Siberia to breed, but young birds will sometimes remain here.
The oldest areas of saltmarsh recovery at Avalon have very dense coverage of samphire shrubs, and we saw more nondescript little brown birds as well as sparrows, scrub wrens, and fairy wrens flitting in and out of bushes. There was also a white-fronted chat, a striking native bird that lives in saltmarsh and other swampy areas. Other identifiable wetland birds at these survey sites included spoonbills, sacred ibis, black swans, and a white-faced heron. In all, at least 13 species were recorded at our 50+ year restored areas.
There were some birds to be found even in the control ponds– unsurprisingly these were mostly waterbirds like red-capped plovers, black-winged stilts, and cormorants. Some white-fronted chats flew through, and there were more sightings of red-necked stints, bringing the total to 5 species for the control area.
But what about the bugs?
Compared to March, where dry conditions on the control ponds yielded a few interesting species like a velvet ant, earwigs, and several species of moth, there were no living bugs to be found in sweeps or by direct search this time.
The bugs collected in sweep netting, beating trays, and direct search, along with the benthic bugs collected in soil cores, are still being processed and identified. However, we did once again find some interesting arachnids such as jumping spiders and sac spiders living in the taller shrubs of the restoration sites.
BugBlitz’s Louis shared with us some of the species he’s identified so far, including a fly-like specimen called a Psocid (“SO-sid”), or booklice. They play an important role in the nutrient cycle by breaking down lichen and algae, making those nutrients available to predators.
There was also this caterpillar of a Tussock Moth- so named because of the long, tussock-like tufts of hair along the caterpillar’s body. In the image you can see two red spots – these are dorsal glands, which secrete a liquid that deters ants from attacking the caterpillars.
In addition to the experts from Bug Blitz Trust overseeing the collection and identification of these bugs, we’ve been adding photographs to the iNaturalist platform. iNaturalist is an online social network for people who love nature – users share images of the species they’ve found, and the community of taxonomic experts and enthusiasts helps with identification. Anyone can then check out what is being observed, where, and when, and hone their ID skills at the same time!
Springing into round 3 of surveys
Spring is always a great time to get out into nature, with many plants displaying their flowers or boosting their growth, and animals becoming more active as the weather warms and food is abundant. We’re very interested to see what birds and bugs are about in the spring!
The next (and final) field trip for the year will be in mid-October. Keep an eye on the GeelongPort citizen science webpage or follow us on social media to stay tuned with further updates including registration details.