Pushmi-pullyu butterfly

The Common Tit (Hypolycaena erylus himavantus) male
The Common Tit (Hypolycaena erylus himavantus) male

Whilst photographing this striking butterfly – The Common Tit (Hypolycaena erylus himavantus) in Thailand – I noticed that it was moving the tails at the end of its wings.  The movement was quite noticeable; the little black ‘tails’ with white tips, moving up and down. This behaviour not only draws attention to the back of the animal, but the tails also look surprisingly like antennae. According to the ‘false head’ hypothesis, butterflies such as these – lycaenids – have evolved the appearance of a false head at the back end, so that predators such as birds, will direct their attacks towards this, the less vulnerable part of the insect (1). The effect is presumably reinforced by the eye-spots at the end of the hind-wings, which may also tempt birds to peck at those places (and not at the head). The tails are best seen in profile, when the black spots on the hindwings – false eyes – are also most apparent (2). So the butterfly becomes a sort of pushmi-pullyu (push-me—pull-you) creature, a  Doctor Dolittle animal with two front ends that looks like it could go either way!

 The Common Tit (Hypolycaena erylus himavantus) male

The Common Tit (Hypolycaena erylus himavantus) male

The male H. erylus himavantus has purple-blue coloured wings with a circular black brand (or circle) on the upperside of the fore-wings, just visible in these photos (above and below); whilst the female has brown wings without a black spot (2).  The black circular mark on the forewing (below) is not particularly distinct, and is not a prominent eye-spot, as such. What it’s function is I have no idea.

The Common Tit (Hypolycaena erylus himavantus )
The Common Tit (Hypolycaena erylus himavantus )

The remarkable thing about this small blue butterfly, is that the larvae are attended by Weaver ants; the ants protect the larvae in exchange for ‘nectar’ secreted by the larvae via a special organ on their back (2). The ants in effect stand guard around the butterfly larvae in exchange for the delicious liquid produced by the caterpillars!  Such associations, between lycaenids and ants are very common, and the butterflies have evolved many interesting ways of manipulating the ants to their (sometimes mutual) advantage (3, 4). Incredibly, the lycaenid butterfly larvae produce a so-called  ‘appeasement song’ – low vibrations which are picked up by the ants via the substrate (plant) – which stop the ants from attacking them, and perhaps even summon the ants if the larvae are threatened!  The pupae also make sounds which have been shown to likewise attract ants and keep them close by to guard the immobile pupa.

These photographs were taken in December 2014, at Doi Chiang Dao, Chiang Mai Province, northern Thailand.

1. Robbins, Robert K. “The” false head” hypothesis: predation and wing pattern variation of lycaenid butterflies.” American Naturalist (1981): 770-775.

2. http://butterflycircle.blogspot.co.uk/2011/09/life-history-of-common-tit.html

3. Pierce, Naomi E., et al. “The ecology and evolution of ant association in the Lycaenidae (Lepidoptera).” Annual review of entomology 47.1 (2002): 733-771.

4. http://www.learnaboutbutterflies.com/Malaysia%20-%20Hypolycaena%20erylus.htm

Skippers

Fullstop swift (Caltoris cormasa) Doi Chiang Dai, Chiang Mai, Thailand
Fullstop swift (Caltoris cormasa) Doi Chiang Dai, Chiang Mai, Thailand

If skippers were dogs, I think they would be pugs!  Skippers are stocky little butterflies with hooked antennae, large eyes and a rapid, bobbing or darting flight.

The Narrow-banded Velvet (Koruthaialos rebecula) with characteristicd hooked antennae
The Narrow-banded Velvet (Koruthaialos rebecula) with characteristic hooked antennae

There are about 3,500 butterflies in the Family Hesperiidae, including skippers, skipperlings, darters, flats,  awls, awlets, and a type known as policemen.  There are only eight species in the UK, and some are quite restricted in distribution.  The small green caterpillars of these UK species mainly feed on grasses.

Small Skipper (Thymelicus sylvestris) male Bedfordshire
Small Skipper (Thymelicus sylvestris) male Bedfordshire

In contrast to our relatively poor skipper diversity, there are many more species in the tropics; for example, 310 or 311 species in the Family Hesperiidae have been recorded from Thailand (1, 2).  They include butterflies with a host of attractive common names, including: Hoppers, Bobs, Aces, Demons, Flitters, Lancers, Palmers, Darts, Flats, Awls and so on (see below and also these websites with some beautiful photographs: 3-8).

The Clavate Banded Demon (Notocrypta clavata clavata)
The Clavate Banded Demon (Notocrypta clavata clavata) Thailand

Flats, so-called because they hold their wings flat while resting (!), are hesperiids in the subfamily Pyrginae.  They are relatively fast-flying butterflies, often found on the undersides of leaves.

Dark Yellow-banded Flat (Celaenorrhinus aurivittata aurivittata Moore, 1878) Thailand
Dark Yellow-banded Flat (Celaenorrhinus aurivittata aurivittata Moore, 1878) Thailand

Skippers are not the most colourful or exotic species of butterfly, but there are many highly attractive and interesting species.  One on the best sites on the internet is the Butterflies of Singapore, which includes some very fine close-up photographs of skippers (8).

1. http://www.malaeng.com/blog/?cat=64

2.  Butterflies of Thailand by Ek-Amnuay, P.

3. http://www.thaibugs.com/?page_id=200

4. https://www.flickr.com/photos/jan_f_rasmussen/sets/72157633356889862/

5. http://flickrhivemind.net/Tags/hesperiidae,thailand/Interesting

6. http://www.ukbutterflies.co.uk/family.php?name=Hesperiidae

7.  http://norfolkbirderinthailand.blogspot.co.uk/2013/04/chiang-dao-butterflies-march-2013.html

8. http://butterflycircle.blogspot.co.uk/search?q=hesperiidae

The Common Earl, a butterfly with green eyes!

Common Earl (Tanaecia julii odilina) male
Common Earl (Tanaecia julii odilina) male

The Common Earl (Tanaecia julii), as the name suggests, is a relatively common butterfly with a wide distribution, including India, Bhutan, Myanmar, Thailand, China, West Malaysia and Sumatra.  It is a butterfly I see regularly whilst walking in Doi Suthep–Pui National Park, Chiang Mai, Thailand, and all of these photographs were taken there, at different times.

Common Earl (Tanaecia julii)
Common Earl (Tanaecia julii) male

There are three subspecies, but the one which occurs in Chiang Mai province is Tanaecia julii subsp. odilinia (1).  The males have lovely chocolate-brown coloured wings, with a broad blue margin on the hind wing.  They look to me like they have been dipped in blue paint!

Common Earl (Tanaecia julii) male
Common Earl (Tanaecia julii) male

The females are slightly larger, with prominent white marks or spots on the forewing and no blue band on the hindwing.  As if to compensate, they have more blue than the males on the undersides of their hindwings!  See below.

Common Earl (Tanaecia julii odilinia) female
Common Earl (Tanaecia julii odilinia) female

What is striking about both sexes of this butterfly, are their lovely green eyes! The males often rest on foliage in the sunshine, where they are relatively easy to photograph, although they do fly off easily if disturbed. They also have a green proboscis to match their eyes!

Common Earl (Tanaecia julii odilina) male
Common Earl (Tanaecia julii odilina) male

1)  Butterflies of Thailand by Pisuth Ek-Amnuay.  ISBN 978-9742891862

Land iguanas: a link with the past

Land iguana (Conolophus subcristatus) Galapagos
Land iguana (Conolophus subcristatus) Galapagos

There are 44 species of iguanas (in nine genera), but remarkably, some are still undescribed (1).  There are three Land iguanas found in The Galápagos Islands: Conolophus marthae, Conolophus pallidus and Conolophus subcristatus. The commonest one, C. subcristatus,  is found on about seven islands, including North Seymour, where these pictures were taken.  I was not fortunate enough to come across the other two species, the yellow and pink species.  Amazingly, the Galápagos pink land iguana, a relic lineage dating back over 5 million years, remained unseen – lurking on Volcan Wolf (the northernmost volcano in Isabela) – until it was “accidentally seen” by some Galápagos National Park rangers in 1986 (2).

Although they play second fiddle to their more illustrious cousins, the marine iguanas, land iguanas are in some ways more impressive.  They can grow quite large – it varies depending on which island they live on – to over a metre in length and weighing up to 13 kg.  They mostly feed on prickly pear cacti (Opuntia) although they also take a range of invertebrates and carrion (hopefully not tourists!).

 Land iguana (Conolophus subcristatus) Galapagos

Land iguana (Conolophus subcristatus) Galapagos

We have not been very kind to land iguanas.  Man introduced goats (which ate their food) and dogs and cats (which killed them); soldiers also used them for target practice.  They have, as a consequence been decimated in number, and native populations on two islands have been lost.  Despite all these trials and tribulations, there are estimated to be still  between 5,000 and 10,000 land iguanas remaining on  The Galápagos Islands and according to the Galapagos Conservancy (GC) “all of the populations appear to be healthy” (3).

 Land iguana (Conolophus subcristatus) Galapagos captive bred.

Land iguana (Conolophus subcristatus) Galapagos captive bred.

These wonderful creatures deserve our respect and protection. Like marine iguanas, they can live for a long time (over 50 years), and have been present on these island for many millions of years. Indeed, it is thought that they diverged from the marine iguanas about 10 million years ago (long before the present islands even existed!).

1) http://www.iucn-isg.org/wp-content/uploads/2013/03/Iguanas_of_the_World_Checklist_v2011-2.pdf

2)  Gentile, Gabriele, et al. “An overlooked pink species of land iguana in the Galápagos.” Proceedings of the National Academy of Sciences 106.2 (2009): 507-511. http://www.pnas.org/content/106/2/507.full

3) http://www.galapagos.org/about_galapagos/reptiles/

A sea-going lizard

Marine iguanas (Amblyrhynchus cristatus sbsp. venustissimus)
Marine iguanas (Amblyrhynchus cristatus sbsp. venustissimus)

Marine iguanas (Amblyrhynchus cristatus) have probably been living happily on the Galápagos islands for over 10 million years (1).  The first human being they saw was the Bishop of Panama in 1535 (2).  I don’t suppose they took much notice!  They look to me like they are not easy to impress.  I guess 10 million years on a bunch of rocks makes you rather laid back!

When I first saw marine iguanas in The Galápagos, I was surprised how small they were.  My expectations were I suppose, formed by close-ups taken by BBC camera crews. The seven subspecies do however, vary considerably in size, as do individuals within a given population.

Marine iguana (Amblyrhynchus cristatus) on Fernandina
Marine iguana (Amblyrhynchus cristatus) on Fernandina

There is nothing more primeval that a pile of iguanas; and they really do lie about in heaps.  One of the guides commented that he fantasizes that someone collects them and piles them up on the beach at the end of each day!  The casual arm draped by one lizard over the back of another, suggests a certain capacity for affection (below).

Marine iguana (Amblyrhynchus cristatus) piled up on Fernandina
Marine iguana (Amblyrhynchus cristatus) piled up on Fernandina

This propensity to cuddle up together, may be a result of thermoregulation:  “A [more] likely explanation for the formation of beach piles is that iguanas gather at spots that offer a slightly better (i.e., warmer) microclimate during the late afternoon hours, when piles usually develop”.  But it may also have something to do with managing ticks, which remarkably enough – given that they take regular dips in the sea – seem to plague these animals (4).  It’s a fascinating subject!

Marine iguanas (Amblyrhynchus cristatus) in a pile on Fernandina
Marine iguanas (Amblyrhynchus cristatus) in a pile on Fernandina

Despite their long residence on these islands, and the existence of a number (7) of different races or subspecies, marine iguanas show relatively little evolutionary divergence (1).  This is probably because, being a sea-going lizard and good swimmers, they have moved or been dispersed between the different islands.  The large males can dive down to 9m for algae in the subtidal zone, but they cool down quickly in the cool waters of the Galápagos archipelago.  Many spend their time feeding on exposed algae in the intertidal zone around low tide, but in total only 5% (a little over an hour) of each day is actually spent close to or in the water (3).  The rest of the time, I guess, they just spend dozing, at least that’s what it looked like to me.  This particular individual – a pinkish variety – was clinging to a rock like  Sisyphus!  Or was he just thinking?  There I go, anthropomorphizing!

Marine iguana (Amblyrhynchus cristatus sbsp.  venustissimus)
Marine iguana (Amblyrhynchus cristatus sbsp. venustissimus)

Marine iguanas have an endearing habit of sneezing (without the use of a handkerchief!).  They blow salt from their noses through a specialised gland which removes it from the salty food they consume.  The salt does however, often remain stuck to their heads, which gives the tops of their heads a sort of white, encrusted look (next two slides, below). Amazingly, the nasal salt glands are capable of removing up to 95% of salt ingested as food or with sea water (5); they are veritable desalination units!

Marine iguana (Amblyrhynchus cristatus sbsp. venustissimus)
Marine iguana (Amblyrhynchus cristatus sbsp. venustissimus)
Marine iguana (Amblyrhynchus cristatus) on Fernandina
Marine iguana (Amblyrhynchus cristatus) on Fernandina

Marine iguanas have all sorts of tricks up their sleeves.  They can shrink down to a more manageable size when food is in short supply (6); they can change colour to reflect their state of randiness (!); and if all goes well, they can live to a ripe old age of sixty (7).  I’m happy to say that there are thought to be a good few hundred thousand Marine iguanas remaining on the Galápagos islands (go count!); but they are subject to predation by invasive cats and dogs, so I hope the next 10 million years will be good for them as the last 10 million.

1)  Rassmann, K., et al. “The microevolution of the Galápagos marine iguana Amblyrhynchus cristatus assessed by nuclear and mitochondrial genetic analyses.” Molecular Ecology 6.5 (1997): 437-452.

2) http://www.galapagosislands.com/galapagos-history/galapagos-modern-history.html

3)  Trillmich, Krisztina GK, and Fritz Trillmich. “Foraging strategies of the marine iguana, Amblyrhynchus cristatus.” Behavioral Ecology and Sociobiology 18.4 (1986): 259-266.

4) Wikelski, M.  (1999).  Influences of parasites and thermoregulation on grouping tendencies in marine iguanas. Behavioral Ecology 10 (1):22-29. http://beheco.oxfordjournals.org/content/10/1/22.full

5)  Shoemaker, Vaughan H., and Kenneth A. Nagy. “Osmoregulation in the Galápagos marine iguana, Amblyrhynchus cristatus.” Physiological zoology(1984): 291-300.

6)  Wikelski, Martin, and Corinna Thom. “Marine iguanas shrink to survive El Niño.”Nature 403.6765 (2000): 37-38.

7) http://www.galapagos.org/about_galapagos/reptiles/

Rock on pigeons, you are just like us!

Feral pigeons (Columba livia domestica) female with chequered plumage
Feral pigeons (Columba livia domestica) female with chequered plumage

Feral pigeons (Columba livia domestica) – also called city pigeons or street pigeons – are extremely successful animals.  They are derived from domesticated pigeons, which are themselves derived from rock doves.  Rock doves nest on cliffs, and are relatively rare.  On the other hand, feral pigeons have successfully adapted to our urban environment, treating buildings like artificial cliffs.  Having gone through the process of domestication and artificial breeding, feral pigeons have a wide range of plumage (1).   Rock doves were probably domesticated by man as far back as 10,000 years ago (2) and this process undoubtedly pre-adapted the feral pigeon to live alongside man.  There are thought to be as many as 20 million feral pigeons in Europe, and worldwide they must number much more. Like us, they have become abundant and widespread.

 Feral pigeons (Columba livia domestica) female with chequered plumage

Feral pigeons (Columba livia domestica) female with chequered plumage

Most people like pigeons – they certainly like feeding them – and in the UK at least, it is an offense to kill or injure a pigeon, or destroy its nest, under the Wildlife and Countryside Act 1981.  Large numbers can be a bit of a problem however, especially in cities, so in some places their numbers probably do need to be controlled.  This is quite a controversial area however, but they are wrongly labelled as spreading disease, although their droppings do cause damage to buildings.

Feral pigeons mate for life and can live for quite a long time, sometimes as much as 20 years!  The sexes can be quite hard to tell apart, until they start mating (!), but the male bird usually has brighter iridescent feathers around the neck (see below).

Feral pigeon (Columba livia domestica) male
Feral pigeon (Columba livia domestica) male

Species which are able to colonise and thrive in the urban environment – unlike many other rare or threatened creatures whose habitat we are destroying – will survive into the future.  If we provide nesting places for them (tall buildings) and abundant food supplies (litter), then they are going to thrive and multiply (3).  You have to admire their adaptability; they have learnt to live with us and in many ways they are much like us: urban, garrulous, greedy, populous and clever!

I photographed these birds in Thailand.  The numerous balconies on the tall hotel building I was staying in provided ideal ledges for them to sit on and survey the surroundings.  Each balcony was also a potential source of food, depending on what tasty scraps or left-overs might have been left out by the occupants of the rooms.  There was a sort of ‘bush telegraph’ system, such that when one bird found some left-over food on a balcony, the others soon followed. There were always some late-comers though, pecking hopefully at the floor even though all the scraps had been cleaned up.  It is sometimes hard not to anthropomorphize!

Pigeons feeding on a hotel balcony
Pigeons feeding on a hotel balcony

1) http://feralpigeonproject.com/guide-to-pigeon-colours/

2) http://www.pigeoncontrolresourcecentre.org/html/about-pigeons.html

3)  Katarzyna Przybylska et al. (2012) Local and Landscape-Level Factors Affecting the Density and Distribution of the Feral Pigeon Columba livia var. domestica in an Urban Environment. Acta Ornithologica 47, (1), 37-45. http://www.bioone.org/doi/abs/10.3161/000164512X653908

Bees love lilies

Water lily (Nymphaea sp.) with Asian hive honeybee ( (Apis cerana)
Water lily (Nymphaea sp.) with Asian hive honeybee ( (Apis cerana)

Whilst taking pictures of water lilies in Queen Sirikit Botanic Gardens (Chiang Mai, Thailand) I noticed that there were bees feeding on the flowers.  Honey bees are generalists and visit a huge range of flowers, which they pollinate whilst feeding on their pollen and nectar.  There are five species of honey bee in Thailand and I think this is one is the Asian hive honeybee (Apis cerana) which is known to feed on lily pollen (1). Bees are not the only insect to feed on lily pollen, but they clearly like these beautiful flowers and perhaps they taste nice as well! What is interesting, was that they were feeding on the pollen before the water lily flower had fully opened.

Water lily with bee

1)  Suwannapong, G., M. E. Benbow & J. C. Nieh, 2011. Chapter 1 – Biology of Thai Honeybees: Natural History and Threats. In: Florio, R. M. (Ed.), Bees: Biology, Threats and Colonies, pp. 1–98.