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Justin Gerlach @jstgerlach.bsky.social · 6d

My latest paper has just been published in PeerJ; working on this one was a really fun puzzle to solve. We identify an extinct predator on Mauritius from the holes it left in shells of its prey.

Mauritian snail shells show evidence of extinct predators
peerj.com/articles/201...
@peerj.bsky.social

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Justin Gerlach @jstgerlach.bsky.social · 9d

As we approach the beginning of the new academic year this year's @peterhousecam.bsky.social Biology Newsletter is now out islandbiodiversity.com/petnewslette...

Justin Gerlach @jstgerlach.bsky.social · 14d

Partula reintroduction comes to an end for 2025 with a final monitoring in lovely Papehue valley on Tahiti. Nothing startling today but lots of newborn snails is encouraging. I really hope we can show success with Partula nodosa next year.
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Justin Gerlach @jstgerlach.bsky.social · 15d

When sorting the shells we found I discovered this: Partula mooreana (first release last year); middle 3 new dead from this year, right one from last year (first evidence of survival for a year). On left unmarked shell of a wild born. Amazing to be so close to population establishment so soon.

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Justin Gerlach @jstgerlach.bsky.social · 15d

Final monitoring on Moorea, and what a day. A good start in the reserve at Fare Natura. Then we found wild-born adult Partula taeniata simulans. I was confident we could do that, so a pleasing find, but...
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Justin Gerlach @jstgerlach.bsky.social · 16d

Last field survey on Tahiti today: the southern point of Te Pari. Nothing unusual but good populations of Partula hyalina marmorata. The sort of patchy metapopulations we found are probably natural for this species (one of few partulids not to be Critically Endangered or Extinct)
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Justin Gerlach @jstgerlach.bsky.social · 18d

Today was a search for high altitude snails on Mt Aorai. Finding snails in this environment isn't easy. We did find some Critically endangered Samoana diaphana. The shell is extremely thin and translucent (hence 'diaphana'), the distinctive pattern is on the body inside the shell
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Justin Gerlach @jstgerlach.bsky.social · 19d

Some encouraging signs for Partula nodosa and affinis today; many released animals found again and many births. We also scouted out possible additional release sites for next year.

Justin Gerlach @jstgerlach.bsky.social · 21d

Partula are always unexpected. Today we visited a relict population of Partula hyalina and Samoana attenuata. What we didn't expect was to find hyalina eating another snail species. There was a carnivorous Partula in the past, but we've never document predation by hyalina before.

Justin Gerlach @jstgerlach.bsky.social · 22d

Today was monitoring day on Huahine island and the last day for most of the team. What a day for a big find! Great results from the releases, but even better was finding this tiny one- the first wild-born Partula on Huahine for 31 years. Another great vindication of everyone's hard work
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Justin Gerlach @jstgerlach.bsky.social · 23d

Today was the last Partula snail reintroduction of the year: Huahine island with more varia and the first rosea to be released since 2019

Justin Gerlach @jstgerlach.bsky.social · 25d

2nd day of monitoring on Moorea; still great progress with good dispersal and very little mortality despite us finding several of the predatory Euglandina. They may be invasive monsters but I still have a soft spot for their elegance (a picture of one instead of Partula for once)

Justin Gerlach @jstgerlach.bsky.social · 25d

The great find of the day was this wild-born Partula tohiveana away from the release site - so we had population establishment last year and now range expansion. I couldn't ask for better results without being greedy!

Justin Gerlach @jstgerlach.bsky.social · 25d

First day of monitoring the released snails on Moorea. Exceptionally good results, for most species there was no mortality at all despite a night of unbelievably heavy rain - not what the zoo snails are used to at all. The snails in the reserve look fantastic

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Justin Gerlach @jstgerlach.bsky.social · 26d

Yesterday was a busy day for Partula conservation. As well as a full day of releases of snails back into the forest on Moorea we had the opening and stocking of the new reserve at Fare Natura. Fantastic to see that go from my wild idea exactly two years ago to this

Justin Gerlach @jstgerlach.bsky.social · 28d

On Raiatea today reintroducing Partula navigatoria descended from the last wild snails I collected in 1991. This was supposed to happen back in 2020. We also found an excellent site for Partula hebe next year (hopefully)
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Justin Gerlach @jstgerlach.bsky.social · 29d

Partula releases today: we are trying a new monitoring technique with Partula nodosa using RFID tags. We also visited Tiapa valley to look for Partula incrassa but without success; that's often the way with Partula field research.

Justin Gerlach @jstgerlach.bsky.social · Sep 8

It's back to the Pacific today: to Tahiti for this year's Partula tree snail reintroductions. We hope to build on least year's success. This year we have participation in the field from London Zoo, Disney's Animal Kingdom and Woodland Park Zoo
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Justin Gerlach @jstgerlach.bsky.social · Aug 26

The collecting for surveying Cambridge college garden biodiversity is complete; now it's identifying the hundreds of insects etc that we've collected. A slight diversion from that work was this visiting sparrowhawk - our sparrows were less than delighted at its sudden appearance.

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Justin Gerlach @jstgerlach.bsky.social · Aug 23

Last major sampling of the Cambridge colleges biodiversity survey today: @selwyn1882.bsky.social. A pond teeming with life, and an overlooked find: Hesperomyces harmoniae fungus that lives only on the invasive harlequin ladybird (those are the little yellow tufts on the back of the beetle)

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Justin Gerlach @jstgerlach.bsky.social · Aug 22

Another day studying biodiversity in Cambridge colleges. A rosy tiger moth at Trinity, woodland @queens.cam.ac.uk and I was hoping for the Cambridge endemic 'Backs goldilocks buttercup' @kingscollege.bsky.social but I can't find out how to identify it, so this photo might be any old buttercup.

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Justin Gerlach @jstgerlach.bsky.social · Aug 21

Top find of today's biodiversity survey of Cambridge colleges was a wasp spider at Trinity College, also wonderful flowers Clare College despite the dry

Justin Gerlach @jstgerlach.bsky.social · Aug 19

Today its been biodiversity assessments in what looks like very interesting long grass habitat in @churchillcol.bsky.social and @trinityhallcamb.bsky.social

Justin Gerlach @jstgerlach.bsky.social · Aug 19

Another week, another set of Cambridge colleges to study. Yesterday we surveyed the biodiversity of Murray Edwards and @fitzwilliamcollege.bsky.social. Two more to do today.

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Justin Gerlach @jstgerlach.bsky.social · Aug 13

And today we sampled habitats in @caiuscollege.bsky.social and @darwincollegecam.bsky.social . A very hot day for hunting insects.

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