Seasonal Update - February 2020


Welcome to the final throes of winter, “the winter that never was” as I have heard it called. Indeed, for much of it, this season hasn’t felt much like winter and, as I write, the temperature outside is 11C (52F), despite it being four hours after sunset in late January. Bar a couple of chilly nights last month, temperatures have remained well above the seasonal average for the month, with even Achfary in the Scottish Highlands recording a daytime high of 18.7C (66F). This represented the Highland’s warmest December temperature on record – slightly above Achnashellach, which recorded 18.3C in December 1948 – and positively balmy in comparison to their seasonal average of 6C (43F). It wasn’t just the UK basking in the warm Azorean air last month, either - Norway was also unseasonably mild, with 19C recorded in Sunndalsora, some 25C (45F) above the monthly average.

The middle of the month saw storm Brendan make landfall, bringing torrential rain and strong winds across the country. Stornoway, off the coast of northwest Scotland, saw 80mph (129 kph) winds. The following day, a similarly deep area of low pressure subjected England to yet more rain and winds touching 70mph (113 kph). This stormy start to the new year was a result of the substantial temperature differential over North America. The western section of the continent was subject to a polar airflow bringing average highs of -8C (18F), while the eastern section was basking in mid-20s Celsius (high 70s F). This temperature contrast super-charged the jet stream, whipping up low pressure systems in the north Atlantic and driving them across the British Isles. A northerly airflow took over after these storms passed, bringing some short term icy weather before a return to a southerly airflow that lifted temperatures again.

These mild winters are, in themselves, nothing particularly unusual, although 2019/20’s does appear to have been particularly mild and wet. What’s more interesting to climate scientists is how frequently we’re seeing these mild seasons - more often, it seems. Similarly, more prolonged hot and dry weather has resulted in critical conditions in several countries, including South Africa and Australia, which is currently experiencing its worst wild fires in living memory. Regarding the Australian bush fires, it is worth mentioning that some were started deliberately (24 people have so far been arrested on suspicion of arson according to official stats from NSW police), but most appear to have been started by lightning and their spread and severity was exacerbated by strong winds, high temperatures and droughts, which have been linked to climate change. Closer to home, a new study published in Global Change Biology last month reported a “significant increase” in the volume of vegetation in all four height brackets of Mount Everest. In other words, Everest is “turning green” as rising temperatures increase the area of land suitable for plant growth.

A highlight of February is male Roe deer (_Capreolus capreolus_) sporting rapidly-growing antlers wrapped in velvet. - Credit: Marc Baldwin

Elsewhere, a team of Canadian chemists at McMaster University discovered a way to break down and dissolve the tyre rubber, raising hopes that it could allow them to be recycled. Meanwhile, biologists at the Max Plank Institute found that early-arriving blue tits had a higher chance of breeding than those turning up to breeding grounds later, and that arrival times predicted several aspects of their breeding success. Finally, University of Georgia researchers carrying out analysis of camera trap photos from around the Fukushima nuclear power plant in Japan found that wildlife is thriving in the exclusion zone nearly a decade after the accident.

If you’re up for getting outside, as usual, the Wildlife Trusts have a series of nature-themed events up and down the country, as do the RSPB. If you feel like being proactive this month and live near the coast, Surfers Against Sewage is looking for people to organise cleans of their local beaches – details here. The Forestry Commission is running a series of events this month – full list here. If you’re interested in the wildlife to be found this month, check out my Wildlife Watching - February page.

Discoveries of the Month

Zoos and cartoons increase public interest in wildlife and conservation

The conservation of wildlife and natural spaces has been drawn to sharp focus in recent years as some of the predicted impacts of climate change have been realised. The engagement of the public, particularly young people, is a vital aspect of any attempt to protect ecosystems and conserve species, but is often difficult to achieve. One element that seems necessary for generating public interest in protecting a given species or habitat is direct engagement with it – visiting that habitat or seeing that species in person. In many cases, direct engagement is difficult, particularly when dealing with disparate species or very rare or dangerous animals.

A keeper at Colchester Zoo clicker training with a chimpanzee. While many dislike zoos, many have a positive conservation impact and new research suggests they have an important role to play in engaging the public with wildlife conservation. - Credit: Steph Powley

One method by which people can connect with wildlife in a safe and controlled environment is in zoos and video programmes. Many take issue with the maintenance of animals in captivity and decry zoos as a cruel relic of a bygone era, but many modern zoos have an increasingly important role to play in species conservation and, according to new research by Japanese zoologists, public involvement.

Yuya Fukano, at the University of Tokyo, and colleagues Yosuke Tanaka and Masashi Soga set out to examine the role of zoos and a cartoon programme in shaping public interest in and support for animals, including threatened species, in Japan between 2011 and 2018. The researchers collected lists of the mammals and birds that are kept in the three major zoos in Japan, with particular reference to endangered species. In the end, they ran their analysis comparing Internet searching within given prefectures with the animals kept in the local zoos for 92 animal species: 63 mammals and 29 birds. Additionally, they analysed how Google searches for particular species were linked to their being featured on the popular Japanese animated show Kemono Friends.

Fukano and his team found that Google searches for the 92 subject species were strongly associated with prefectures holding them in their zoo collections. Indeed, when accounting for things like wages, percentage of students at uni and the age of the populations, their data show that searches for a species within a particular prefecture increased as the number of zoos in that prefecture holding the species increased. Similarly, searches and WikiPedia page views for species featured on Kemono Friends were also higher, suggesting that the TV show drove active engagement with these species. Perhaps of more importance was that the number of animal adoptions and donations also increased and, in their paper to Science of the Total Environment this month, the biologists explain:

Importantly, we showed that an increase in public interest may induce actual financial support for conservation—the broadcast of a TV program featuring animated animals increased donations for ex situ populations of animals in zoos. Our results indicated that both zoos and animated TV programs may be able to contribute to improving biodiversity conservation programs by increasing public interest in, and support for, animals.

Reference: Fukano, Y. et al. (2020). Zoos and animated animals increase public interest in and support for threatened animals. Sci. Tot. Environ. 704: 135352 (doi: 10.1016/j.scitotenv.2019.135352)

Mowing for wildlife: cutting your lawn less often increases biodiversity

A well-maintained lawn used to be a matter of pride in rural villages, with people spending hours mowing, trimming and edging the turf in pursuit of that perfect finish. In recent years, however, there has been something of a shift towards artificial lawns that look like grass but come maintenance-free. Once the preserve of city football club pitches and tennis courts, artificial (i.e. plastic and, typically polyethylene, polypropylene or polyamide) grass has become increasingly popular in recent years as a neat and hassle free alternative to the real thing, having grown into an international business worth an estimated £2bn ($2.5bn) in 2016.

Many of us take pride in our lawns, but mowing them less often can help increase their biodiversity. - Credit: Sean Hobson (CC BY 2.0)

Unfortunately, fake lawns are rather at odds with the current requirement for an increase “rewilding” to help mitigate some of the impacts of climate change, particularly flooding. Indeed, while artificial lawns have no impact on water retention, grass lawns absorb a considerable amount of water, slowing down its transfer through the area and reducing the potential for flooding. Fortunately, following a collection of stories in the press regarding this trend, many are now more aware of the advantages that a lawn can have, and new research from Canadian scientists suggests that how we care for our lawns, and specifically how often we drag the mower out of the shed, can have a big impact on their value to wildlife.

A team of biologists at the Université du Québec à Trois-Rivières, led by Chris Watson, set about searching the scientific literature for studies on experimental lawn management within an urban setting in order to conduct their meta-analysis. In other words, they took all these data, stuck them together, and fed them into a statistical model to looked for trends. In all, they reanalysed the data of 14 studies conducted in various locations in North America and Europe between 2002 and 2018, looking in particular at how the frequency of mowing affected ecology of the lawn - the bugs living and plants growing in/on it.

The study, currently in press with the Journal of Applied Ecology, found that as the frequency of mowing increased, so too did the number of “pest” species (e.g. scarab larvae, ragweed, dandelions), while the density and diversity of other invertebrates (e.g. bees, earthworms, carabid beetles, grasshoppers/crickets, etc.) and plant species declined. Frequent mowing, as expected, was found to consistently remove the tall reproductive structures such as flowering stems, favouring low-growing annual and biennial species, reducing the structural complexity for invertebrates as well as the species diversity and litter dynamics. Overall, this leads to less soil enrichment.

So, mowing less often increases the plant species diversity, rather than favouring grass and low-growers, and this has a knock-on impact for insects, particularly pollinating beetles and bees that are drawn to the flowering stems. Better still, mowing less can save councils money. In their economic assessment of one location in Canada, based on costs of contractors mowing lawns, costs could be reduced by 36% if the number of cuts per area were reduced by only five per year. In their paper, Watson and his colleagues conclude:

Increasing urban biodiversity and reducing greenhouse gas emissions are strong motivators for reducing lawn management intensity. We also suggest that the benefits of reducing pest species while saving lawn management costs may provide additional social and economic incentives for decision makers to review urban greenspace management practices.”

Reference: Watson, C.J. et al. (2020). Ecological and economic benefits of low-intensity urban lawn management. J. Appl. Ecol. In Press. (doi: 10.1111/1365-2664.13542)

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