City Nature Challenge 2019

May 9 · 6 min read

by Thomas Gomersall

It’s a common gripe among older generations and nature enthusiasts that people today spend too much time on their phones and not enough time outside connecting with the environment. But the two aren’t mutually exclusive when it comes to the City Nature Challenge.

Held from 26–29 April this year involving nearly 160 cities, City Nature Challenge (CNC) is an annual, all-inclusive competition for observers to take and upload as many photos of [preferably wild] animals and plants as possible using the free mobile phone app, iNaturalist. They are then uploaded into a giant database [along with the date, time, location and name of photographer] that later determines which city wins the competition in such categories as “Most Observations [photos taken]”, “Most Species Logged” and “Most Observers Taking Part”.

Started in 2016 in Los Angeles, the CNC has quickly grown into a global event, with participation increasing from just 68 in 2018 to 159 cities in 2019. While most of these cities are in the Americas, Hong Kongers have proven keen iNaturalist users with more than 5,000 signed up in Hong Kong as of 18 April. More surprising still is the number of wildlife observations. At CNC 2018, Hong Kong recorded 20,628 observations of 2,932 species, out of over 420,000 observations of 19,000 species recorded worldwide. “We genuinely did shock the world with this,” said Shaun Martin, CNC coordinator for Hong Kong and Macau. “I had phone calls [about it] from other organisers from different cities”

For this year, Hong Kong came in 10th place for observations (logging 31,144), second for number of species logged (3,596), and ninth for number of observers taking part (1,120). The results show a major leap from last year’s place for number of species, and despite initial appearances, the numbers of observations and observers still saw increases of up to 50 per cent from 2018.

Numbers aside, the CNC also provides other, more important conservation opportunities. With a global increase in urbanisation comes an urgent need to understand its effects on biodiversity, particularly in Asia where these effects have been largely understudied. The CNC has a vital role in filling these knowledge gaps by determining what species exist in and around urban Hong Kong. Having ordinary citizens collect this data could also help the Hong Kong government carry out some of their own conservation policies outlined in the 2016 Biodiversity Strategy and Action Plan (BSAP).

“A big part of [BSAP] is promoting community involvement,” said Martin. “However, the government really didn’t elaborate on how this will happen because the big irony is that it’s actually against the law to capture species anywhere, which doesn’t exactly help if you’re with a school going out to do surveys. But of course there’s nothing illegal about taking a picture.”

I attended two of several events organised by WWF-Hong Kong, at Hong Kong Park and Island House, focusing on the weeds, herbs, epiphytes and fungi (Island House’s lawn is full of the latter) growing in the shadows of the bigger plants and sometimes even on them. And there were other surprises, too.

“Look for insects that go up the trees” said Martin as we strolled beneath the canopy of Hong Kong Park. “Sometimes you find ants, sometimes you find beetles, sometimes you find caterpillars. You just never know.” Sure enough, a chocolate pansy butterfly soon alighted on a nearby bush and I snapped my first photo of that day on iNaturalist.

Indeed, with my self-imposed restrictions on plant photography, insects became the most noticeable life form to me. Like all the best apps, iNaturalist quickly becomes addictive and soon every tiny, flickering movement was drawing my eye to the undergrowth and I vigorously scanned the bushes, trees and flowers for any sign of life. On many occasions, my efforts were rewarded with the sight, though not always a photograph, of an insect. Some were too small and secretive for the camera to focus on properly. Others, like the swallowtail butterfly that I spent a good 10-15 minutes scrambling after, would fly away before the camera could focus on them at all.

But there were also those that were easier to photograph, like the oriental latrine flies on Island House’s shoreline, too drawn to the stench of decaying fish carcasses to care about the intrusion of my phone camera. Or the glistening pink and blue dragonflies that basked obligingly on the boulders fringing Hong Kong Park’s lily pond, similarly unfazed by my presence. And while some birds such as the Asian koels and yellow crested cockatoos sat high atop the tallest trees, others were more obliging including the ground-pecking sparrows and spotted doves.

At a group identification session that I attended following the close of competition, I learned that there was strong school participation this year, mostly international but also a few local ones, with Ta Kwu Ling Ling Ying Public School a particularly notable example of the latter, recording 447 observations of 140 species.

And with 4,000 of the roughly 30,000 observations taken with no species identification attached to them, it was left to experts in Hong Kong taxa such as John Allcock and Roger Kendrick to help. The session was also personally informative, including when Kendrick informed me that one of my submissions, which I was sure was a wasp, was actually a member of the similar-looking soldier fly family. “You see these things often enough and you start to be able to identify them at a glance” said Kendrick of his impressive abilities.

Martin says that despite the drop in the city’s ranking, Hong Kong still has much to be proud of. “We may have dropped down a place or two [from last year], when you put into perspective that there’s about 90 more cities competing this year, maintaining a place on the top 10 list is still pretty good.”

Minor frustrations aside, this year’s CNC was a lot of fun. Martin was an excellent coordinator at both of the events I attended and his enthusiasm and competitive spirit are infectious. I hope, as does he, that this will inspire participants to continue cataloguing Hong Kong’s biodiversity using iNaturalist long after CNC.

Tips for iNaturalist users

· No photos of pets, potted plants, crops, livestock or humans.

· Take photos of real plants and animals.

· Make sure your GPS is on when using iNaturalist, otherwise your location will not register.

· If you don’t know the photographed species, don’t leave the identification section blank as this makes it harder for other iNaturalist users to find and identify. Even something as simple as “plant” or “insect” is better than nothing.

Panda blog @WWF-Hong Kong

WWF contributors share daily insights on Hong Kong biodiversity and WWF-Hong Kong projects


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WWF contributors share regular insights on Hong Kong biodiversity and conservation issues

Panda blog @WWF-Hong Kong

WWF contributors share daily insights on Hong Kong biodiversity and WWF-Hong Kong projects