Marcus Chua
@marcuschua.bsky.social
Studies and curates mammals of SE Asia. Biodiversity, conservation, and natural history museums. Also swims, hifi, and ramen.
Same handle on the x-bird app.
🇸🇬
https://sites.google.com/view/marcuschua
Same handle on the x-bird app.
🇸🇬
https://sites.google.com/view/marcuschua
Why it matters: Losing a dominant generalist (wild pig) can trigger ecological cascades—altered understory, seed dispersal and species interactions. We saw diet overlap (fallen 🌼) suggesting competition.
Long-term monitoring of forest habitats is essential as wild pigs recover.
Long-term monitoring of forest habitats is essential as wild pigs recover.
November 28, 2025 at 7:27 PM
Why it matters: Losing a dominant generalist (wild pig) can trigger ecological cascades—altered understory, seed dispersal and species interactions. We saw diet overlap (fallen 🌼) suggesting competition.
Long-term monitoring of forest habitats is essential as wild pigs recover.
Long-term monitoring of forest habitats is essential as wild pigs recover.
15-year trend: mouse-deer encounter rates rose 2.4x from 2009→2019, then 5.5x from 2019→2024 post-ASF.
Predicted densities: ~31/km2 (2009), ~67/km2 (2019), measured 293/km2 (2024).
Wild pigs vanished from transects in 2024 but camera traps show re-establishment at ~30/km2.
Predicted densities: ~31/km2 (2009), ~67/km2 (2019), measured 293/km2 (2024).
Wild pigs vanished from transects in 2024 but camera traps show re-establishment at ~30/km2.
November 28, 2025 at 7:27 PM
15-year trend: mouse-deer encounter rates rose 2.4x from 2009→2019, then 5.5x from 2019→2024 post-ASF.
Predicted densities: ~31/km2 (2009), ~67/km2 (2019), measured 293/km2 (2024).
Wild pigs vanished from transects in 2024 but camera traps show re-establishment at ~30/km2.
Predicted densities: ~31/km2 (2009), ~67/km2 (2019), measured 293/km2 (2024).
Wild pigs vanished from transects in 2024 but camera traps show re-establishment at ~30/km2.
How we measured it: Intensive night transects and camera trap distance sampling.
Both estimates converged—transects: 293/km2 (CV 0.12), cameras: 264/km2 (CV 0.22)
We also validated a model linking encounter rates to density to track trends when full surveys aren’t feasible.
Both estimates converged—transects: 293/km2 (CV 0.12), cameras: 264/km2 (CV 0.22)
We also validated a model linking encounter rates to density to track trends when full surveys aren’t feasible.
November 28, 2025 at 7:27 PM
How we measured it: Intensive night transects and camera trap distance sampling.
Both estimates converged—transects: 293/km2 (CV 0.12), cameras: 264/km2 (CV 0.22)
We also validated a model linking encounter rates to density to track trends when full surveys aren’t feasible.
Both estimates converged—transects: 293/km2 (CV 0.12), cameras: 264/km2 (CV 0.22)
We also validated a model linking encounter rates to density to track trends when full surveys aren’t feasible.
[New paper] After the 2023 African Swine Fever outbreak, greater mouse-deer density on Pulau Ubin, Singapore surged to 293/km2—the highest known for the species.
Likely drivers: >98% wild pig mortality, active reforestation and low predation pressure.
doi.org/10.1016/j.bi...
Likely drivers: >98% wild pig mortality, active reforestation and low predation pressure.
doi.org/10.1016/j.bi...
November 28, 2025 at 7:27 PM
[New paper] After the 2023 African Swine Fever outbreak, greater mouse-deer density on Pulau Ubin, Singapore surged to 293/km2—the highest known for the species.
Likely drivers: >98% wild pig mortality, active reforestation and low predation pressure.
doi.org/10.1016/j.bi...
Likely drivers: >98% wild pig mortality, active reforestation and low predation pressure.
doi.org/10.1016/j.bi...
RIP boots: 2015–2025
I didn’t expect we’d be such close friends again, protecting me through two big whale defleshing ops.
I didn’t expect we’d be such close friends again, protecting me through two big whale defleshing ops.
October 23, 2025 at 12:21 PM
RIP boots: 2015–2025
I didn’t expect we’d be such close friends again, protecting me through two big whale defleshing ops.
I didn’t expect we’d be such close friends again, protecting me through two big whale defleshing ops.
It’s been a month into the salvage of the roqual whale, with the days long and I’ve been onsite daily during workdays.
So touched by my colleagues showing concern about my wellbeing, feeding and hydration. Still don’t know who the snacks are from but thanks!
So touched by my colleagues showing concern about my wellbeing, feeding and hydration. Still don’t know who the snacks are from but thanks!
October 18, 2025 at 11:27 AM
It’s been a month into the salvage of the roqual whale, with the days long and I’ve been onsite daily during workdays.
So touched by my colleagues showing concern about my wellbeing, feeding and hydration. Still don’t know who the snacks are from but thanks!
So touched by my colleagues showing concern about my wellbeing, feeding and hydration. Still don’t know who the snacks are from but thanks!
The organizing committee created a fun photo booth with “Team Vert” and “Team Invert”—what a way to start a war!
September 6, 2025 at 2:16 AM
The organizing committee created a fun photo booth with “Team Vert” and “Team Invert”—what a way to start a war!
The LKCNHM Public Research Symposium 2025 is underway!
My colleagues and I will be sharing about specimens, science and stories from the museum with members of the public, and I will be giving a talk and moderating a panel discussion.
Excited to share our science and research!
My colleagues and I will be sharing about specimens, science and stories from the museum with members of the public, and I will be giving a talk and moderating a panel discussion.
Excited to share our science and research!
September 6, 2025 at 2:16 AM
The LKCNHM Public Research Symposium 2025 is underway!
My colleagues and I will be sharing about specimens, science and stories from the museum with members of the public, and I will be giving a talk and moderating a panel discussion.
Excited to share our science and research!
My colleagues and I will be sharing about specimens, science and stories from the museum with members of the public, and I will be giving a talk and moderating a panel discussion.
Excited to share our science and research!
Enter the introduced domestic cat. 🐈
Our analysis shows their skulls overlap significantly with SE Asian native species, especially female leopard cats and marbled cats. This creates a new, direct threat of competition for food and space.
Our analysis shows their skulls overlap significantly with SE Asian native species, especially female leopard cats and marbled cats. This creates a new, direct threat of competition for food and space.
August 15, 2025 at 6:06 PM
Enter the introduced domestic cat. 🐈
Our analysis shows their skulls overlap significantly with SE Asian native species, especially female leopard cats and marbled cats. This creates a new, direct threat of competition for food and space.
Our analysis shows their skulls overlap significantly with SE Asian native species, especially female leopard cats and marbled cats. This creates a new, direct threat of competition for food and space.
For other cats, it's more complex. We found clear skull morphology overlap, suggesting competition for similar food.
Female Asian golden cats & male jungle cats have similar skulls, pointing to niche overlap.
But they seem to avoid competition by using different habitats.
Female Asian golden cats & male jungle cats have similar skulls, pointing to niche overlap.
But they seem to avoid competition by using different habitats.
August 15, 2025 at 6:06 PM
For other cats, it's more complex. We found clear skull morphology overlap, suggesting competition for similar food.
Female Asian golden cats & male jungle cats have similar skulls, pointing to niche overlap.
But they seem to avoid competition by using different habitats.
Female Asian golden cats & male jungle cats have similar skulls, pointing to niche overlap.
But they seem to avoid competition by using different habitats.
Some cats are specialists. The fishing cat and flat-headed cat have highly distinct skulls, adapted for hunting fish. 🐟
This unique diet means they seldom compete with other native cats for food, occupying their own ecological niche.
This unique diet means they seldom compete with other native cats for food, occupying their own ecological niche.
August 15, 2025 at 6:06 PM
Some cats are specialists. The fishing cat and flat-headed cat have highly distinct skulls, adapted for hunting fish. 🐟
This unique diet means they seldom compete with other native cats for food, occupying their own ecological niche.
This unique diet means they seldom compete with other native cats for food, occupying their own ecological niche.
[New paper] How do 8 small wild cat species coexist in SE Asia? Do they avoid competition by carving out unique niches?
Our study analyzed 465 museum skulls to see how their anatomy helps them share the space. 🧵
doi.org/10.1038/s415...
/w @wildcru.bsky.social @ntlmuseumsscot.bsky.social
Our study analyzed 465 museum skulls to see how their anatomy helps them share the space. 🧵
doi.org/10.1038/s415...
/w @wildcru.bsky.social @ntlmuseumsscot.bsky.social
August 15, 2025 at 6:06 PM
[New paper] How do 8 small wild cat species coexist in SE Asia? Do they avoid competition by carving out unique niches?
Our study analyzed 465 museum skulls to see how their anatomy helps them share the space. 🧵
doi.org/10.1038/s415...
/w @wildcru.bsky.social @ntlmuseumsscot.bsky.social
Our study analyzed 465 museum skulls to see how their anatomy helps them share the space. 🧵
doi.org/10.1038/s415...
/w @wildcru.bsky.social @ntlmuseumsscot.bsky.social
A story on the leopard cat in Singapore is featured in Our Wild Neighbours by Yap Seow Choong (in Chinese). Also honored to be featured as a wildlife researcher in it!
Available in bookstores and online stores.
Available in bookstores and online stores.
July 10, 2025 at 6:04 AM
A story on the leopard cat in Singapore is featured in Our Wild Neighbours by Yap Seow Choong (in Chinese). Also honored to be featured as a wildlife researcher in it!
Available in bookstores and online stores.
Available in bookstores and online stores.
We often hear of humans feeding wildlife, but occasionally the tables are turned!
Towers et al. reviews attempts by wild killer whales to provision people with food items.
Fish, a whole seal, and even seaweed!
I want to be fed by a killer whale!
dx.doi.org/10.1037/com0...
Towers et al. reviews attempts by wild killer whales to provision people with food items.
Fish, a whole seal, and even seaweed!
I want to be fed by a killer whale!
dx.doi.org/10.1037/com0...
July 4, 2025 at 10:57 AM
We often hear of humans feeding wildlife, but occasionally the tables are turned!
Towers et al. reviews attempts by wild killer whales to provision people with food items.
Fish, a whole seal, and even seaweed!
I want to be fed by a killer whale!
dx.doi.org/10.1037/com0...
Towers et al. reviews attempts by wild killer whales to provision people with food items.
Fish, a whole seal, and even seaweed!
I want to be fed by a killer whale!
dx.doi.org/10.1037/com0...
It’s been a memorable month:
Finally finished my mouse-deer dissertation and defense
Qualified for the World Aquatics Masters Championships in SG 2025
Mayhem in Singapore
Penang
Really grateful for everyone who was part of this.
Finally finished my mouse-deer dissertation and defense
Qualified for the World Aquatics Masters Championships in SG 2025
Mayhem in Singapore
Penang
Really grateful for everyone who was part of this.
June 21, 2025 at 5:55 AM
It’s been a memorable month:
Finally finished my mouse-deer dissertation and defense
Qualified for the World Aquatics Masters Championships in SG 2025
Mayhem in Singapore
Penang
Really grateful for everyone who was part of this.
Finally finished my mouse-deer dissertation and defense
Qualified for the World Aquatics Masters Championships in SG 2025
Mayhem in Singapore
Penang
Really grateful for everyone who was part of this.
Super fascinating Han et al. (2025) found leopard cats occupied human settlements in China for 3,500 years before domestic cats in 600-900 CE.
Evidence include ancient DNA and this super cute 168 BC painting of a supposed leopard cat.
Also, a co-author's name is Miaomiao.
doi.org/10.1101/2025...
Evidence include ancient DNA and this super cute 168 BC painting of a supposed leopard cat.
Also, a co-author's name is Miaomiao.
doi.org/10.1101/2025...
May 22, 2025 at 2:12 PM
Super fascinating Han et al. (2025) found leopard cats occupied human settlements in China for 3,500 years before domestic cats in 600-900 CE.
Evidence include ancient DNA and this super cute 168 BC painting of a supposed leopard cat.
Also, a co-author's name is Miaomiao.
doi.org/10.1101/2025...
Evidence include ancient DNA and this super cute 168 BC painting of a supposed leopard cat.
Also, a co-author's name is Miaomiao.
doi.org/10.1101/2025...
I thought it'll be a uniquely Singapore thing, but someone else found leopard cats on reclaimed land—in South Korea!
Lee et al. (2025) tracked leopard cats on grassland and rice fields but they seem to avoid areas of human use.
Adapted 🛰️ maps by me.
doi.org/10.1007/s133...
Lee et al. (2025) tracked leopard cats on grassland and rice fields but they seem to avoid areas of human use.
Adapted 🛰️ maps by me.
doi.org/10.1007/s133...
May 19, 2025 at 7:59 PM
I thought it'll be a uniquely Singapore thing, but someone else found leopard cats on reclaimed land—in South Korea!
Lee et al. (2025) tracked leopard cats on grassland and rice fields but they seem to avoid areas of human use.
Adapted 🛰️ maps by me.
doi.org/10.1007/s133...
Lee et al. (2025) tracked leopard cats on grassland and rice fields but they seem to avoid areas of human use.
Adapted 🛰️ maps by me.
doi.org/10.1007/s133...
It’s the animal with the floofiest tail, the tufted ground squirrel (Rheithrosciurus macrotis)—found only on Borneo!
The grooved teeth is thought to act like a sawing surface to break down tough nuts, which are part of its diet.
The grooved teeth is thought to act like a sawing surface to break down tough nuts, which are part of its diet.
May 8, 2025 at 3:16 PM
It’s the animal with the floofiest tail, the tufted ground squirrel (Rheithrosciurus macrotis)—found only on Borneo!
The grooved teeth is thought to act like a sawing surface to break down tough nuts, which are part of its diet.
The grooved teeth is thought to act like a sawing surface to break down tough nuts, which are part of its diet.
Tap and zoom.
Whose teeth is this?
Whose teeth is this?
May 8, 2025 at 1:50 PM
Tap and zoom.
Whose teeth is this?
Whose teeth is this?
I’d like to thank this reviewer who completed their review of our manuscript in one day (!); even before the other invited reviewer responded.
[just hoping it wasn’t a negative one 🤣]
Also this tracking portal is like receiving an Amazon order.
[just hoping it wasn’t a negative one 🤣]
Also this tracking portal is like receiving an Amazon order.
April 28, 2025 at 6:30 PM
I’d like to thank this reviewer who completed their review of our manuscript in one day (!); even before the other invited reviewer responded.
[just hoping it wasn’t a negative one 🤣]
Also this tracking portal is like receiving an Amazon order.
[just hoping it wasn’t a negative one 🤣]
Also this tracking portal is like receiving an Amazon order.
Looks like another albino or leucistic mouse-deer has been recorded, this time in Vu Quang National Park in Viet Nam.
From the looks and location, it is likely what we recognise as the lesser mouse-deer (Tragulus kanchil).
vnexpress.net/cheo-cheo-ba...
From the looks and location, it is likely what we recognise as the lesser mouse-deer (Tragulus kanchil).
vnexpress.net/cheo-cheo-ba...
March 27, 2025 at 11:03 AM
Looks like another albino or leucistic mouse-deer has been recorded, this time in Vu Quang National Park in Viet Nam.
From the looks and location, it is likely what we recognise as the lesser mouse-deer (Tragulus kanchil).
vnexpress.net/cheo-cheo-ba...
From the looks and location, it is likely what we recognise as the lesser mouse-deer (Tragulus kanchil).
vnexpress.net/cheo-cheo-ba...
[New paper] An albino Malayan greater bamboo bat—possibly the first record of albinism in this bamboo hollow-roosting group.
Yes, he's very cute. Unfortunately, he was found in a shoe cabinet and didn't make it. Now a specimen in our museum's mammal collection.
lkcnhm.nus.edu.sg/wp-content/u...
Yes, he's very cute. Unfortunately, he was found in a shoe cabinet and didn't make it. Now a specimen in our museum's mammal collection.
lkcnhm.nus.edu.sg/wp-content/u...
March 2, 2025 at 6:47 PM
[New paper] An albino Malayan greater bamboo bat—possibly the first record of albinism in this bamboo hollow-roosting group.
Yes, he's very cute. Unfortunately, he was found in a shoe cabinet and didn't make it. Now a specimen in our museum's mammal collection.
lkcnhm.nus.edu.sg/wp-content/u...
Yes, he's very cute. Unfortunately, he was found in a shoe cabinet and didn't make it. Now a specimen in our museum's mammal collection.
lkcnhm.nus.edu.sg/wp-content/u...
Wow that’s so big and fluffy! Definitely real hard work.
This cannot compare: I only prepared a lesser mouse-deer yesterday. Just 1 kg.
This cannot compare: I only prepared a lesser mouse-deer yesterday. Just 1 kg.
February 7, 2025 at 3:45 AM
Wow that’s so big and fluffy! Definitely real hard work.
This cannot compare: I only prepared a lesser mouse-deer yesterday. Just 1 kg.
This cannot compare: I only prepared a lesser mouse-deer yesterday. Just 1 kg.
Just reviewed a revised manuscript for a mammal journal where it appears that I'm the only reviewer.
I've submitted and reviewed for the journal before and there were always at least 2 reviewers.
Is that the norm now, are reviewers so hard to find, are standards slipping, or all the above?
I've submitted and reviewed for the journal before and there were always at least 2 reviewers.
Is that the norm now, are reviewers so hard to find, are standards slipping, or all the above?
February 4, 2025 at 6:39 AM
Just reviewed a revised manuscript for a mammal journal where it appears that I'm the only reviewer.
I've submitted and reviewed for the journal before and there were always at least 2 reviewers.
Is that the norm now, are reviewers so hard to find, are standards slipping, or all the above?
I've submitted and reviewed for the journal before and there were always at least 2 reviewers.
Is that the norm now, are reviewers so hard to find, are standards slipping, or all the above?
Made this Chinese horror-scope 12 years ago. After a full zodiac cycle, it’s relevant again.
Context: In 2013 the government released plans that a new train line would cut across a nature reserve. Nature folks were concerned. Through engagement, the plans were made more sensitive to nature.
Context: In 2013 the government released plans that a new train line would cut across a nature reserve. Nature folks were concerned. Through engagement, the plans were made more sensitive to nature.
January 31, 2025 at 6:17 AM
Made this Chinese horror-scope 12 years ago. After a full zodiac cycle, it’s relevant again.
Context: In 2013 the government released plans that a new train line would cut across a nature reserve. Nature folks were concerned. Through engagement, the plans were made more sensitive to nature.
Context: In 2013 the government released plans that a new train line would cut across a nature reserve. Nature folks were concerned. Through engagement, the plans were made more sensitive to nature.