Category Archives: Biodiversity

A once in a lifetime sunset?

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It’s been a curious year in the UK, weather wise, with an early, mild spring interspersed by sudden cold snaps that may (or may not) have had a profound impact on pollinators, and then a summer that was hotter and drier than any in living memory. There’s been some amazing thunderstorms and torrential rains, and weeks when there was no rain at all. Then, on Thursday evening, as Karin and I were coming back from a walk around Abington Park (via a quick stop in the pub) the heavy, rain-bloated skies conspired with the setting sun to produce, for a brief period, a display of light and clouds that was more vibrant and gorgeous than any I’ve ever seen. The sky reflecting from the rain-soaked pavements of Northampton added further drama to what may well be a once in a lifetime experience.

Here are a few shots I managed to take using the camera on my phone; I’ve not altered the colour or played with images in any way, but they do partial justice to the quality of the light that evening.

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Pollinators, landscape and friends: our recent trip to the Danish island of Sejerø

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This is not the first time I’ve written about the beautiful Danish island of Sejerø – see my post “Why do bumblebees follow ferries?“. It’s home to our friends Pia and Stephen Valentine (Stephen is the very talented artist who produced the fabulous study of waxwings that Karin commissioned for my birthday last year). Earlier this month we traveled over to stay with them and to explore some more of the island. Here are some photos and thoughts from that trip.

Despite the hot, dry weather that northern Europe has been experiencing recently there were pollinators aplenty. Thistles and knapweeds (both groups from the daisy family Asteraceae) are well known to be drought tolerant and attract a lot of insect interest. This is a Pantaloon Bee (Dasypoda sp.) If it was Britain I’d say that it was D. hirtipes, but there are other species on the continent so I can’t be sure. These bees are well named: the “pantaloons” are found only on the females and are used to collect pollen, especially from Asteraceae.

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I believe that this is the male of this species; note the absence of the pollen-collecting hairs on the rear legs and the yellow face, typical of many male bees:

The flower heads of the knapweeds were highly sought after; on this one, two different bumblebees (Bombus spp.) were competing with two Silver Y moths (Autographa gamma):

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Sometimes the bumblebees got an inflorescence to themselves, though the photobombing Silver Ys were never far away:

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It’s been a good year for the Silver Y, large numbers have migrated northwards from southern Europe and we’ve had lots in our garden too. On Sejerø they were everywhere, on all kinds of plants:

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The butterfly is one of the Blues (Lycaenidae), possibly Common Blue (Polyommatus icarus), but again this being Denmark they may have other species that I’m not familiar with. Note the Silver Y photobombing once more…:

Wild carrot (Daucus carota) was common on the island and always attracts a wide range of flies, wasps and beetles:

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Close to home we found a huge cherry tree laden with the fruits of pollination and collected a couple of kilos for Stephen to make into jam. Stoning them was messy but fun and a nice opportunity to sit and chat about nature and people:

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I was very impressed with Stephen’s up-cycled general purpose baskets, made from plastic containers he finds on the beach, wire, and lengths of old hosepipe:

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Along the shore another edible plant, Sea Kale (Crambe maritima) was attracting a lot of attention from white butterflies (Pieridae) whose caterpillars feed on this and other members of the cabbage family (Brassicaceae):

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I tried a piece of raw leaf; it tasted ok, salty and a little bitter. Apparently it’s very nice if you blanch the young leaves. It’s a distinctive and impressive component of the beach flora:

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Amidst the greens, buffs and browns of the beach landscape we encountered the occasional scarlet of a patch of poppies (Papaver sp.):

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Everywhere on the island we saw evidence of the link between life on land and in the sea, and the cycles and processes upon which that life depends. Sand martins (Riparia riparia – an apt name – “riparian” refers to the interface between land and water) are common and their nest excavations speed up the return of sediments back to the sea:

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Favoured rocks have been used by gulls and other sea birds for generations, their guano helping to enrich these coastal waters and fueling the primary production of seaweeds and diatoms, which in turn feed other shore life:

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Evidence of human activities was never far away, though, concrete and steel blending with nature:

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Wheat fields merging with the sky:

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Thanks to Pia and Stephen, and of course Zenja, for making this such a wonderful trip and allowing us to join them in exploring their home island:

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The impact of building a new university campus on urban bird diversity and abundance: a seven-year study

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Over the past few years I’ve posted several pieces about how colleagues, students and myself have been monitoring one aspect of the environmental impact of the University of Northampton’s brand new 22 ha, £330 million Waterside Campus development. Specifically we have been looking at how the construction work has affected bird diversity and abundance in and around the site: see my posts “An interim report on the Waterside bird surveys” and “Monitoring the impact of the new Waterside Campus“.

Our approach has been to repeat the baseline bird surveys (three winter and three spring) that were done in 2012/13 as part of the environmental impact assessment prior to work taking place. The new campus opens this summer and, following our most recent set of surveys in April/May, it’s time to reveal our findings so far. Here are the headlines:

The baseline surveys recorded a total of 52 bird species. In the following graphs birds have been categorised according to their RSPB Red, Amber, Green status. Four species from the original surveys remain unrecorded: Marsh tit, Bullfinch, Collared dove, and Lesser whitethroat. However at least two of these (Bullfinch and Collared dove) are still found within 1km of the site.

During the repeat surveys we have recorded an additional 25 species that were not found in the baseline surveys. This is not surprising – bird assemblages are dynamic, given that most species are very mobile – but it’s still interesting to find that so many more species are finding homes in the area. If the four “missing” species return then the potential full diversity of the site is at least 77 species:

Waterwide birds - RAG

However this overall good news story is more complex than it first appears. In the graph below I have plotted the Simpson’s Index for each survey, with a LOESS regression showing 95% confidence limits. Simpson’s Index combines the data on both the number of species and their abundance to provide an overall measure of the impact of the construction work. It’s clear that during the main phase of construction the average bird diversity per survey dropped significantly. Following the completion of the noisiest and most disruptive activities, diversity has started to return to its pre-construction levels:

Waterside Simpsons

This overall assessment hides a lot of detail; as you can see below, Green status birds have fared best, Amber status birds have done ok; Red status birds have fared worst, especially in spring, but better in winter:

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The bird diversity is not quite back to what it was, but overall our findings are very encouraging. In the initial phases of the development we talked with the landscape architects about adding ecological value to Waterside by including more native trees, reed beds, wild flower meadows, etc. We’ve yet to assess how these features will affect biodiversity on the site, including birds, but we might predict that the final diversity exceeds that of the original brownfield site. With that in mind we will be doing at least one more cycle of three winter and three spring surveys during 2018/2019.

Long-term monitoring of this kind is almost never undertaken for infrastructure projects of this nature. Universities, I would argue, need to take a lead in promoting such activities and making then a common component of the planning process. From this work I think that our main conclusion is that redevelopment of peri-urban brownfield sites such as this doesn’t have to mean a loss in biodiversity, at least not as far as the birds are concerned. We also plan future surveys of mammals, plants and invertebrates to assess how they are doing.

My thanks to all the colleagues and students who have been involved in the work so far: Duncan McCollin, Janet Jackson, Joanne Underwood, Kirsty Richards, Suzy Dry, Charles Baker, Pablo Gorostiague, Andrew Hewitt.

To finish, here are some photographs that we took of the work being carried out so you can see the scale of what has been achieved at Waterside:

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An inordinate fondness for “an inordinate fondness for”: origin of an over-used title element

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There is an oft-told story about the biologist JBS Haldane. Sitting with a group of theologians over dinner he was asked what his studies of the natural world had led him to conclude about God. After a pause, Haldane replied “He has an inordinate fondness for beetles”. The story is almost certainly apocryphal, though Haldane was fond of saying similar things – see this dissection of the evidence for example.

True or not, it’s a nice story that does in fact say something profound about the Earth’s biodiversity: beetles (Coleoptera) are far more species-rich than almost any other Order of insects. I say “almost” because the Dipterologists are convinced that the true flies (Diptera) have more species. And they may well be correct given that flies are less well studied than beetles, and a 4 ha area of tropical forest in Costa Rica can support an astounding 4,332 species, with the prediction that many more would be found with further sampling.

Regardless of the accuracy of the quote and of the statistics underlying it, the phrase “an inordinate fondness for” has inspired quite a number of titles of academic papers, chapters, and books – here’s some examples:

Fisher (1988) An inordinate fondness for beetles. Biological Journal of the Linnean Society

May (1989) Ecology – an inordinate fondness for ants. Nature

Evans & Bellamy (1996) An inordinate fondness for beetles. Henry Holt & Co.

Rouse et al. (2018) An inordinate fondness for Osedax (Siboglinidae: Annelida): Fourteen new species of bone worms from California. Zootaxa

Sochaczewski (2016) An inordinate fondness for beetles. The hero’s journey of Alfred Russel Wallace. In: Naturalists, Explorers and Field Scientists In South-East Asia And Australasia. Book Series: Topics in Biodiversity and Conservation

Thomas et al. (2015) Charles A. Triplehorn: an inordinate fondness for darkling beetles. Coleopterists Bulletin

Vieira et al. (2014) Toward an inordinate fondness for stars, beetles and Lobophora? Species diversity of the genus Lobophora (Dictyotales, Phaeophyceae). New Caledonia Journal of Phycology

Clare et al. (2014) An inordinate fondness for beetles? Variation in seasonal dietary preferences of night-roosting big brown bats (Eptesicus fuscus). Molecular Ecology

Dyer et al. (2014) New dimensions of tropical diversity: an inordinate fondness for insect molecules, taxa, and trophic interactions. Current Opinion in Insect Science

Kasson et al. (2013) An inordinate fondness for Fusarium: phylogenetic diversity of fusaria cultivated by ambrosia beetles in the genus Euwallacea on avocado and other plant hosts. Fungal Genetics and Biology

Mann et al. (2013) An inordinate fondness? The number, distributions, and origins of diatom species. Journal of Eukaryotic Microbiology

Chase (2013) An inordinate fondness of rarity. PLoS Biology

Harmon (2012) An inordinate fondness for eukaryotic diversity. PLoS Biology

Hamuli & Noyes (2012) An inordinate fondness of beetles, but seemingly even more fond of microhymenoptera! Newsletter of the International Society of Hymenopterists

Eide (2012) An “inordinate fondness for transporters” explained? Science Signaling

Snider et al. (2012) An inordinate fondness for rocks: roosting habits of bats at Mesa Verde National Park, Colorado. Bat Research News

Longino & Snelling (2009) An inordinate fondness for things that sting. Journal of Hymenoptera Research

Maderspacher (2008) Genomics: an inordinate fondness for beetles. Current Biology

Sandvik (2006) An inordinate fondness for Mecopteriformia. Systematics and Biodiversity

Grove & Stork (2000) An inordinate fondness for beetles. Conference: Celebration Symposium on A World of Beetles: Canberra, Australia.

Ashworth, Buckland & Sadler (1997) Studies in Quaternary entomology: an inordinate fondness for insects. John Wiley.

Bamber & Błażewicz-Paszkowycz (2013) Another inordinate fondness: diversity of the tanaidacean fauna of Australia, with description of three new taxa. Journal of Natural History

I’m sure there’s other that I missed, but you get the idea. The phrase “an inordinate fondness for” seems to be a bit over-used now and I wonder whether some of these papers might have benefitted from a more descriptive title? The title one chooses for a paper or a book really matters – see this old Small Pond Science blog post on the topic. I’m sure that there’s research published showing that papers with titles which describe their findings are more frequently cited but I can’t immediately find it. Perhaps one of my readers knows?

Hunting the Chequered Skipper: an encounter with England’s latest species reintroduction project

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If you have been following recent conservation news on social media you’ll know that this week was an important one for invertebrates. The Chequered Skipper, a butterfly last seen in England in 1976, has been reintroduced to the country as part of the Back From the Brink initiative. The Chequered Skipper project is led by Butterfly Conservation and a team travelled to a site in Belgium earlier in the week where about 40 skippers were captured. These insects were transported back to the UK where they were held overnight in mesh cages at a secret location in order to acclimatise them, then released into the wild. The release was filmed as part of next week’s BBC Springwatch series – look out for it.

The exact location of the reintroduction is secret. However I can tell you that it’s occurred in the Rockingham Forest area of north Northamptonshire, in habitat that (over the past couple of years) has been managed specifically for this reintroduction, in order to create a network of sites across which the species could disperse in the future. This area was the last stronghold of the species in England prior to its extirpation. No one knows why it went extinct here, but hung on and did well in Scotland, but it may relate to climate: 1976, as many of the middle-aged will remember, was a very hot, dry summer, and this butterfly likes it warm and humid.

Yesterday I had the privilege of seeing this reintroduction first hand when I visited the site with my colleague Dr Duncan McCollin. Duncan and I are supervising a PhD student, Jamie Wildman, along with Prof. Tom Brereton, Head of Monitoring at Butterfly Conservation (BC), and the University of Northampton’s Visiting Professor in Conservation Science. Jamie’s project will focus on understanding the habitat requirements for Chequered Skipper, and monitoring the success of the reintroduction. I’m also hoping that it might be possible for Jamie to assess the role of this species as a pollinator of the plants it visits. Butterflies as pollinators is a very under-researched area.

Here’s a shot of the Four Mus-skipper-teers* just before we set off to help BC volunteers to locate the skippers and record their behaviour:

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The day started unpromisingly. It was cool and overcast, and little was flying except some hardy Common Carder Bees. But around lunchtime things began to warm up and gradually the sun broke through and we started to see flying Lepidoptera that we excitedly chased, only to be disappointed by yet another Mother Shipton or Silver Y. But no skippers.

As we encountered some of the BC volunteers who were also tracking the insects we were told that we had “just missed one” or that they “saw one down that ride, we marked the spot”. One volunteer wanted to show me a photo of a Chequered Skipper that he’d just taken “so I could get my eye in”. I politely refused; I wanted to see the real thing and didn’t want to jinx it with a digital preview.

Finally, our efforts were rewarded and we found the first skipper of several we later encountered. The image at the head of this post is that butterfly, a sight that has not been seen in England in more than 40 years. An exciting and privileged encounter. The county Butterfly Recorder, David James (on the right in this next shot), is ecstatic that the reintroduction has occurred “on his patch” but also nervous at the responsibility it represents:

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Later we spent time helping Jamie follow a female skipper who was showing egg-laying behaviour, moving slowly for short distances along a shrubby edge, occasionally nectaring on Bugle, and diving deep into the vegetation to (we hope) oviposit on grass leaves:

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Although I’ve over-cropped this next image of the skipper on Bugle, I thought I’d leave it as I like the different textures and patterns, and the slightly blurry ambience:

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The primary aim of Butterfly Conservation’s project is to return a small part of England’s lost biological heritage. But it’s about more than just the Chequered Skipper. It’s also about understanding how managing a network of sites for this flagship species can benefit other organisms. The wide woodland rides that have been created are packed with plant species, amongst them at least five grasses that could be used as caterpillar food sources for the skippers, plus more than 20 nectar sources were flowering that they (and other flower visiting insects) could use. Those other insects were plentiful too: over the day I spotted five species of bumblebees, several different day flying moths, lots of Dark-edged Bee Flies, and a few different solitary bees and syrphids flies. We heard calling cuckoos, and four different warblers: chiffchaffs, garden warbler, whitethroats, and blackcaps. Red kites (another incredibly successful species reintroduction) floated overhead skimming the treetops as they their cried to one another.

Rockingham Forest is a lovely part of Northamptonshire, well worth a visit. The Chequered Skipper will be a wonderful addition to its biodiversity. Of course there are no guarantees that the reintroduction part of the project will be a success, but if it isn’t it won’t be because of a lack of commitment from the people involved. If the population does become established then in the future the location will be made public and butterfly enthusiasts will be able to come and pay homage to one of the few butterflies with a pub named after it.

*You get the puns you deserve on this blog…..

The explosion in orchids as houseplants: what does it tell us about how flowers evolve?

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One of the major trends in horticulture over the last 20 years or so has been the rise in popularity of orchids as house plants. Orchids used to have a reputation as being delicate, choosy, costly things that needed expensive glasshouses, heating, and humidity systems to grow. Some groups of orchids are certainly like that, but many are not (Orchidaceae is one of the two largest families of plants, after all). These days it’s impossible to walk into any supermarket or department store and not see orchids for sale at a reasonable price, orchids that are tough and can withstand the relatively dry, centrally heated houses in which most of us in Britain live.

The majority of these orchids are varieties of Phalaenopsis, the moth orchids. Intensive hybridisation by commercial growers has meant that there is an almost inexhaustible range of flower colours, shapes, sizes and patterning available. Take a look at this gallery of images and you’ll see what I mean, or go into a shop that sells such orchids and observe that almost no two are alike.

This is the stuff of natural selection: genetic variation in the phenotype that can be acted upon by a selective agent. In this case it’s the growers of orchids who choose the most attractive types to sell and discard the others. If this variation emerged in wild populations most of it would disappear over time, but some, just occasionally, would be selected for by a different group of pollinators and go on to form a new species. This is much more likely to happen if the individuals with this variation are isolated from the rest of the population in time or space, for example if they flower later or have been dispersed to a distant valley or mountaintop (termed allopatric speciation). But it can also happen within populations – sympatric speciation.

Back in 1996, near the start of this orchid explosion, one of my earliest papers was a speculative commentary in Journal of Ecology called “Reconciling ecological processes with phylogenetic patterns: the apparent paradox of plant-pollinator systems”. It generated some interest in the field at the time and has picked up >250 citations over the years, mostly other researchers using it as supporting evidence for the discrepancies we see when trying to understand how flowers evolve within a milieu of lots of different types of potential pollinators selecting for possibly diverse and contradictory aspects of floral form. In that paper I made a passing comment that I expected the reviewers to criticise, which they did not. Once it was published I thought that perhaps other researchers in the field would critique it or use it as a jumping off point for further study, which has not really happened either. This is what I wrote:

“It appears that pollination systems are labile and may evolve quite rapidly….plant breeders can obtain a fantastic range of horticultural novelties through selective breeding over just a few generations.”

This is horticulture holding up a mirror to the natural world and saying: “This is how we do it in the glasshouse, look at the variety we can produce over a short space of time by selecting for flower forms; can nature do it as quickly, and if so what are the mechanisms?”

I still believe that pollination ecologists could learn a lot from horticulture and there’s some fruitful (flowerful?) lines of enquiry that could be pursued by creative PhD students or postdocs. Here’s one suggestion: part of the reason why these Phalaenopsis orchids are so popular as house plants is that they have very long individual flower life times, often many weeks. Now we suspect that floral longevity is under strong selection; see for example research by Tia-Lynn Ashman and Daniel Schoen in the 1990s. This showed that there is a negative correlation between rate of pollinator visitation and how long flowers stay open. Plants with flowers that are not visited very frequently stay open much longer, for example the bird-pollinated flowers of the Canary Islands that may only be visited once or twice a day, and which can remain open for more than 20 days. Is the floral longevity shown by these orchids (or other groups of plants that have been horticulturally selected) beyond the range found in natural populations? If so, what are the underlying physiological mechanisms that allow such extreme longevity? If not, does this mean that there is an upper limit to the lifespan of flowers, and if so, why?

In the mean time I’m going to enjoy the orchids above that sit on our kitchen windowsill. They actually belong to my wife Karin who has developed something of an interest in them in recent months. The big spotty one is a late birthday gift for her that I picked up this morning from a local flower shop, and which stimulated this post as I was walking home. I’d bet that we never see another one like it!

Speaking about plant-pollinator research and science blogging in Wageningen in May

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If any of you are near Wageningen University on 31st May I’m giving a talk about some of our recent research called “The macroecology and macroevolution of plant-pollinator interactions”. It’s preceded by a workshop on the whys and hows of science blogging. Details are in the poster.

Here are the abstracts for the talk and the workshop:

Macroecology and macroevolution of plant-pollinator interactions

Plant-pollinator relationships are an ecologically critical form of interaction that ensures the long-term survival of the majority of the world’s plants species, and contribute to a large fraction of global agricultural output. In additiondiversity and abundance of biotically pollinated plant species can be an important determinant of the diversity of animals at higher trophic levels.

Despite that global significance, most studies of plant-pollinator interactions are done at a local level, involving populations and communities of species, over modest time scales. The ways in which these local sets of interactions scale up to produce global macroecological and macroevolutionary patterns, and the processes underpinning them, will be explored using two case studies.

The first is a data set of 67 plant communities, ranging from 70ºN to 34ºS, with which we investigated the roles of biotic and abiotic factors as determinants of the global variation in animal versus wind pollination. Factors such as habitat type, species richness, insularity, topographic heterogeneity, current climate and late-Quaternary climate change were investigated. The predictive effects of these factors on the proportion of wind- and animal-pollinated plants were examined (see: Rech et al. 2016 – Plant Ecology & Diversity 9: 253-262).

Since these results were published we have increased the number of plant communities in our database to >90, and our findings seem to be robust to these additional data. The dominant influence of contemporary climate on the relative importance of wind-pollinated species suggests that communities may be sensitive to future climate change. Communities in areas that are predicted to become drier may in time contain more wind-pollinated plants which may in turn reduce the diversity of pollinator species that are present. There may also be implications for the prevalence of human pollen allergies. Future work will focus on these two areas.

The second case study uses a newly assembled database of pollinators of the family Apocynaceae (one of the ten largest families of flowering plants), supported by a molecular phylogeny of the major clades. This database has been used to explore phylogenetic and biogeographic patterns of pollinator exploitation (Ollerton et al. in review). The findings from this study challenge some long-held assumptions about convergent evolution, the role of rewards such as nectar, and the notion that some specialised pollination systems are evolutionary “dead ends”. It also highlights the function of novel floral features in determining pollinator type and behaviour, such as the fused gynostegium and pollinia found in the subfamily Asclepiadoideae. In summary, Apocynaceae is emerging as an important model family for understanding the ecology and evolution of plant-pollinator interactions.

Blogging for EEB: why bother?

A growing number of scientists in Ecology and Evolutionary Biology (EEB) have their own blogs or post as guests on others’ blogs. In this workshop we will explore motivations and strategies for blogging, and its advantages for early career researchers. Why blog? What does it do for one’s career? Is it a distraction from actually doing science? How does one build a blog readership? We will also focus on two aspects that are sometimes seen as mutually exclusive: blogging as science outreach to the general public (sci-communication), versus blogging with other professional scientists in mind (sci-community). As preparation for the seminar please read Saunders et al. (2017) Bringing ecology blogging into the scientific fold: measuring reach and impact of science community blogs

Why conservation is like paella: thoughts and photos from our Tenerife field trip

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A couple of days ago I posted a photograph on Facebook with a comment that “after a hot day of collecting data there’s nothing better than a nice big Tenerife paella!”:

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My wife Karin and I had ended up in the small town of Candelaria, tired and hungry after sweating our way through the Malpais de Guimar counting and measuring plants. Big plates of hot food were just what we needed!

After I posted the image a Spanish colleague commented that the dish was “closer to being an arroz con cosas than a paella”. The term translates as “rice with things” and is used to convey the fact that the original Valencian dish of paella has been bastardised and changed across the Spanish-speaking world, and no longer reflects its culinary tradition. Knowing nothing of that culinary tradition I took a look at the Wikipedia entry for paella. It makes for interesting reading, not least the fact that in the original dish one of the main ingredients was the meat of water voles and that the dish was cooked on an open fire fuelled by wood from orange and pine trees to give a distinctive smoky flavour. There was also a lot of geographic variation in the dish, so what constitutes an authentic paella is debatable.

Although there was no sign of rodent flesh or naked flames in the dish that we ate, it was certainly delicious! But the comment about arroz con cosas got me thinking about shifting baselines in cooking and conservation.

The idea of a shifting baseline is that expectations of what is “correct” or “normal” or “natural” change over time depending upon what each generation has experienced. It’s been mainly applied in conservation; for example, the Lake District of England is seen by many as a “natural” landscape of rolling hills and low mountains, but originally it would have been covered in deciduous forest. Likewise large parts of Tenerife contain a high proportion of alien plants (such as agave and prickly pear) but local people and visitors see this as natural. The baseline of “naturalness” has shifted for people. Returning these landscapes to their original condition would mean a drastic shift in the composition of the vegetation. And what point do we return that condition to? One hundred years ago? One thousand? Ten thousand? It’s an issue that is widely debated in the conservation literature, especially in relation to rewilding.

Likewise, over time paella has evolved and been adapted by different chefs, and what is currently cooked in restaurants only partially reflects how the dish was originally cooked. Other than for epicurean purists, our culinary expectations have changed. There’s been a shift in the paella baseline.

Anyway, enough metaphorising, here are some photographs from our trip. To set the context, University of Northampton students and staff, including Pablo Gorostiague who is visiting from Argentina, and colleagues from the University of Sussex (Maria Clara Castellanos and Chris Mackin), were out with us last week. Then we bade them farewell on Sunday before moving on to do some field work.

Field work on the lava fields at Santiago del Teide:

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The landscape of Malpais de Guimar, which actually probably hasn’t changed much in the last 10,000 years:

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How many people can you fit around Pino Gordo, the largest Pinus canariensis on the island:

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The endemic Tenerife Blue Chaffinch:

The cold, damp laurel forest:

Team Nicotiana! Helping Chris with locating Tree Tobacco populations for his PhD work:

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Pablito takes a break:

The flowers, the bees, and the tractor: a true story

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Yesterday I was up and out early with colleagues and students to carry out the first of this season’s spring bird surveys of the University of Northampton’s new Waterside Campus – see my previous post on this topic. We had finished one stretch of the survey and were walking back along the path next to Midsummer Meadow when I spotted a huge expanse of Red Dead-Nettle (Lamium purpureum), mixed in with some While Dead-Nettle (Lamium album):

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Both species produce a lot of nectar; as kids we would often suck it from the flowers of White Dead-Nettle, and they are just as attractive to bees and other pollinators:

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Sure enough, a quick survey showed that there were at least two species of bee working the flowers, Common Carder Bees (Bombus pascuorum), and male and female Hairy-footed Flower Bees (Anthophora plumipes) – here’s a shot of the female:

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Suddenly there was an exclamation from one of my colleagues: whilst I was focused on the bees he’d seen a tractor pulling a grass cutter coming towards us:

Tractor 4 2018-04-18 08.25.06

It got closer…:

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…and closer…:

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…and we were sure it was going to mow this beautiful patch of wild flowers, and the bees, into oblivion:

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But it didn’t! The driver carefully mowed round the patch and headed back the way he’d come:

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A big relief!

Urban recreational grasslands like this clearly need to be managed by regular cutting, but this should be done strategically as these sorts of wild flower patches are important nectar and pollen sources for urban pollinators. They are especially critical at this time of year when resources are needed to build up colony numbers in the social species like Common Carder Bee. I don’t know who manages Midsummer Meadow – presumably contractors working on behalf of Northampton Borough Council? But I hope that this is a conscious strategy by them to conduct “smart mowing” whereby they cut around flower patches like this even when they are not planted. The bees (and I) thank you for it.

Trait evolution, resource specialization and vulnerability to plant extinctions among Antillean hummingbirds – a new study just published

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Hummingbird bowl from BM

Hummingbirds are fascinating creatures and important pollinators for a wide range of plants in the New World (and, historically, possibly in the Old World – see this post from 2014: There were hummingbirds over the White Cliffs of Dover). During the last decade I have been involved in some hummingbird-related research with several colleagues, particularly Dr Bo Dalsgaard and Dr Stella Watts, and it’s generated some really interesting findings about the biogeography, macroecology, and interactions with plants of these most elegant of birds.

The latest installment of this work is a test of some ideas relating to the vulnerability of hummingbirds on islands to the extinction of their plant partners. It’s just been published and the reference is:

Dalsgaard B., Kennedy J.D., Simmons B.I., Baquero A.C., Martín González A.M., Timmermann A., Maruyama P.K., McGuire J.A., Ollerton J., Sutherland W.J. & Rahbek C. (2018) Trait evolution, resource specialization and vulnerability to plant extinctions among Antillean hummingbirds. Proceedings of the Royal Society series B (in press)

Here’s the abstract:

Species traits are thought to predict feeding specialization and the vulnerability of a species to extinctions of interaction partners, but the context in which a species evolved and currently inhabits may also matter. Notably, the predictive power of traits may require that traits evolved to fit interaction partners. Furthermore, local abiotic and biotic conditions may be important. On islands, for instance, specialized and vulnerable species are predicted to be found mainly in mountains, whereas species in lowlands should be generalized and less vulnerable. We evaluated these predictions for hummingbirds and their nectar-food plants on Antillean islands. Our results suggest that the rates of hummingbird trait divergence were higher among ancestral mainland forms before the colonization of the Antilles. In correspondence with the limited trait evolution that occurred within the Antilles, local abiotic and biotic conditions—not species traits—correlate with hummingbird resource specialization and the vulnerability of hummingbirds to extinctions of their floral resources. Specifically, hummingbirds were more specialized and vulnerable in conditions with high topographical complexity, high rainfall, low temperatures and high floral resource richness, which characterize the Antillean Mountains. These findings show that resource specialization and species vulnerability to extinctions of interaction partners are highly context-dependent.

As always I’m happy to send a PDF to anyone who drops me an email.