2024

2024 felt like the year that the lab finally returned to “normal” following the COVID19 years. There was a lot of travel, for fun and for work. I started the year in the UK (Cambridge) finishing my sabbatical. I then visited the Philippines, Thailand, Vietnam, Japan, Malaysian Borneo (field course!), Cameroon, the US (both coasts), peninsular Malaysia, and a few trips to Mainland China. I collected a lot of great memories and made good progress on a number of developing research projects.

A number of milestones occurred in that Yuet Fung Ling received his PhD, Portia Wong her MPhil, and Adam Lee his MSc. Portia and Adam left for PhDs in North America this summer while Fung has remained in the lab to continue working on danaid butterfly migration research. Ying Chen also joined the lab to develop the lab’s research efforts in genomics.

The lab has been productive this year and, truthfully, it was difficult to choose three papers/stories to highlight for the end of the year. Some of the “runner up” papers include 1) a global study on fungal diversity published in Nature for which Michel Dongmo contributed some key data from Cameroon, 2) a cross-lab (with Louise Ashton and Caroline Dingle) collaborative review on tropical urban ecology in Biotropica, and 3) one of Pauline Dufour’s thesis chapters on projections of climatic suitability for some South African lizards (and the importance of considering temporal and spatial resolution) published in Ecology and Evolution.

And so, here is an annual behind the scenes look to some of the key papers to come out of the lab this year:

Coronavirus dynamics associated with the trafficking of Sunda pangolins through Hong Kong

Brian Worthington (left, photographed in Cameroon) and Portia Wong (right, photographed in Palawan) led the investigation into sarbecovirus exposure of pangolins in Hong Kong.

The story behind this paper in BMC Biology is a long and interesting one! My hope is that the longer version of story will come out next year (stay tuned). But to sum up briefly, in early 2020 I teamed with Tommy Lam in the School of Public Health at HKU through Brian Worthington, who was doing a PhD on zoonotic viruses at the time (Brian previously worked in my lab as a research assistant some years prior). We decided it would be worthwhile to test pangolin meat seized in Hong Kong for coronaviruses. We went to work straight away and Portia Wong, at the time an undergraduate, joined our team soon after this.

We knew this project would not be simple, especially in the midst of growing pandemic. To do this properly we needed expertise from virologists, serologists, veterinarians, ecologists, geneticists, and more. Slowly but surely, we grew our broad international team and tested 89 pangolin carcasses seized in the trade.

First, we found that none of the pangolins texted positive PCR for coronavirus infection. So, then we looked to serology. This took many months and we used to different assays to confirm our results. One individual among the 89 tested positive based on both serological methods while a few other individuals were regarded as putatively seropositive based on the fact that one method was positive but the other method was ambiguous.

These results themselves are interesting and fit well with other similar studies on pangolin trafficking and coronaviruses. But what I think is really intriguing about our approach is that we also analyzed the genomics of the pangolins themselves to track down the origin of the individuals. Portia led this part of the study and discovered that while most of the pangolins came from a single seizure, the pangolins from that seizure actually came from multiple parts of the distribution of Sunda pangolins. Additionally, we were able to determine that the individual that was seropositive originated from Java.

This is the first joint paper to come out of my collaborative efforts with Tommy Lam, Maria Zhu, Brian Worthington and others from the School of Public Health. It won’t be the last though and I’m eager to learn more about the synergistic opportunities in ecology, conservation, and public health.

Habitat heterogeneity has negligible impact on bird diversity within small urban parks

Melanie (Chocolate) Chan (center) and me during a meetup in the UK (Cambridge) during my sabbatical in early 2024. And also a Chinese bulbul (left).

Melanie Chan, aka Chocolate, left my lab in 2019 to start her PhD at the University of Exeter. She started her MPhil in 2016, co-supervised by Cascade Sorte and Regan Early – her research project was designed to be part of a larger research effort to examine comparative dynamics of exotic species (this ultimately wasn’t funded, and didn’t really materialize as planned). Chocolate set out to test the “area- heterogeneity” hypothesis in Hong Kong urban parks. Basically, the idea is that while heterogeneity is generally regarded as a good thing for biodiversity, maybe it actually breaks up important habitat area in some places and could be detrimental in some contexts. And Chocolate had good reason to believe that this might be the case in urban parks.

She spent most of 2016 and 2017 collecting the data. Toby Tsang and Caroline Dingle also joined the project around this time to assist with data interpretation and analysis (along with Regan and Cascade). When everything was finished, Chocolate found that there was no statistically significant effect of heterogeneity on bird diversity in the urban parks. If anything, there was a small (but not significant) positive effect, counter to our expectations. On the other hand, she also found that the habitat area of things like water and shrub coverage did affect bird diversity. This has a range of interesting implications for the management of urban green areas for bird diversity.

I know I’m biased but I think this is such a cool finding and that Chocolate executed a very elegant, hypothesis-driven piece of research. So why did it take eight years to get from data collection to publication? Well, mostly bad luck. Editors and peer reviewers can be mean and near-sighted at times… and even in the best of times, the process can be inefficient. However, Chocolate’s persistence paid off, and the editor and peer reviewers of Urban Forestry & Urban Greening helped guide the work to publication this year. I’m very pleased to see this out now!

Vertical forest structure as a key component of habitat suitability for some tropical butterflies

Martha Ledger (the one in the hat) enjoying a party with coauthors Yuet Fung Ling (the tall one), Emily Jones (to Martha’s right, and my left), Kit Lee (top left) and other lab party people.

Ever since arriving to Hong Kong in 2012, I’ve been puzzled by a trend of new species of butterfly establishing themselves in Hong Kong. Over the years, climate change has been targeted as the primary driver attributed to the influx of new species. I suspect climate change is partly to blame. But I’ve also always had a suspicion that the growth of forests in Hong Kong (which is quite substantial) might also be partly to “blame”.

Martha Ledger happily took the task in investigating this with the use of remote sensing tools. We realized that the availability of LiDAR data (3D data of vegetation across the entirety of Hong Kong) in both 2010 and 2020 could help to reveal possible links between forest growth and butterfly habitat suitability. Remarkably, using this data, Martha found that the mean growth in canopy height in that ten-year period was 0.8m. So, how did this affect butterfly habitat suitability?

Well, as it often goes in ecology, the answer was species dependent. We focused on six species that have recently (since 2000) become established. All six species increased habitat suitability between 2010 and 2020 but all for different reasons. Some of the species had distributions linked to vertical habitat structure increases but others had distributions linked to urbanicity and land-use changes. In any case, the study, published this year in Remote Sensing in Ecology and Conservation, provides a nice example of how to use 3D vegetation structure in understanding changing species distributions, which will be particularly important for tropical species who are often dependent on vertically complex forests.

Conclusion

Grace featured as the lab’s mascot between 2012 and 2024. She served the lab faithfully for 12 years but sadly passed away at the age of 16 this year. Always the goofball, constantly finding new ways to engage with mischief, she was and still is a true inspiration.

As with 2024, I’m expecting great science and fun to come out of 2025. In fact, a couple of very cool papers from the lab are in press now and should be available any day (keep an eye on Global Change Biology and Biological Reviews). A number of postgraduates will be wrapping up their degrees in 2025. I also have a lot of teaching to do this year, more than most. I’m excited to dive back in (I didn’t teach much this past semester) and try out some new things in the classroom.

I hope you have a great 2025! So many conservation challenges and so little time. But our lab will keep chipping away, and working towards the preservation of biodiversity wherever we can. We’re also going to keep having fun while we do it.

The Grace face.