Monday, 15 February 2016

The Seri Tanjung Pinang Otter superfamily



What Otters?
There is a lot of misinformation about the otters seen around the coast of the island of Penang. They have been variously described as Sea Otters, Beavers and Sea Lions….both by the press and local passersby who fortunately don’t pretend to be David Attenborough. There are only 13 species of Otters in the world and only three of these are found in South East Asia…namely; Hairy-nosed Otters (I have seen them in Taman Negara), Small-clawed Otters (seen as high as Fraser’s Hill) and the species we have on our shores…the Smooth-coated Otters. Sea Otters are those cute Otters seen around Monterey Bay in the USA and they don’t extend to these parts. The only advantage them being Beavers would be they might gnaw down a few palm oil trees.

The local Smooth-coated Otter species should not be identified on the appearance of the pups because they are two-toned and look similar to adult Small-clawed otters with the white chin. There is however a large difference in size between the two species. 
http://www.bing.com/videos/search?q=Baby+Smooth-coated+otters&view=detail&mid=65B0EB3167CA6C4CA3E865B0EB3167CA6C4CA3E8&FORM=VIRE5
http://www.bing.com/videos/search?q=Baby+Smooth-coated+otters&&view=detail&mid=3D03A17060494B3EE3013D03A17060494B3EE301&rvsmid=65B0EB3167CA6C4CA3E865B0EB3167CA6C4CA3E8&FORM=VDFSRV&fsscr=0



The otters shown below are Smooth-coated Otters. The markings on the lower lip are signatures for individuals





What Locations?
My wife and I have lived in Seri Tanjung Pinang for nearly 5 years. I have seen and photographed Smooth-coated Otters on Penang mainland but the group I am writing about here is a local group that I have observed and photographed on many walks along the promenade of my estate. They have been variously filmed teasing paddling dogs on nearby beaches and feeding along the shoreline. https://www.youtube.com/watch?v=Vu1KrKOWFfM They possibly don’t crave human proximity but have made use of structures created by man. The section of the Straits of Malacca that separates mainland Penang from the island of Penang has many moods and the sunrises peeking over the hills behind Butterworth are often the target on early morning photographers. The sky above has many colours too with huge storm clouds and lightening dancing within clouds. The Seri Tanjung Pinang promenade, despite some local miscreants using it as a motorcycle track is a great asset for house owners on the estate to walk in the early morning to enjoy some nature or to observe the  Straits Quay fireworks that are are also the best locally to herald the new calendar year.



Blue-tailed Bee-eater

White-throated Kingfisher

Whimbrel (an immigrant)

Water Monitor

Black-naped Oriole











The Otter family
I am a scientist and a nature photographer but this story has no scientific rigor in that to verify statements I would have to dart individual animals and do DNA analysis on them. Currently I would rather shoot them with my camera. I have pieced together various observations in the last 6 months that make some sense of many observations I have made and had reported to me in the past 4 years.

Smooth-coated Otters
Smooth-coated Otters are distributed throughout south Asia. Its distribution is continuous from Indonesia, through Southeast Asia and westward from Southern China to India and Pakistan with an isolated population in Iraq. They are often found in large groups where the basic family group consists of an adult female and her offspring and the father of the offspring. The older siblings may also join the group. The Smooth-coated otters attain sexual maturity at 22 months and females deliver first litters at 4 years of age. They mate during August to October. Mating occurs in the water and occurs several times daily. Littering takes place in November-December with the average litter size being 3. Cubs are seen out of the den in February. Males may mate with as many as 4 different females.
The above data was recorded from captive breeding, which correlates well with observations in the wild in India.



My observations.
I have seen pairs of otters in the offshore waters in August and have observed them copulate…..it is over in 15 seconds!!!! 


We have observed otters regularly around the Straits Quay area mainly around Christmas. In the 2015-2016 period I walked the promenade around 6.30-7.30am on most mornings. In late December I could hear the high-pitched squeaking of otters at the Straits Quay Marina.
The video shown is taken from a drone over the Straits Quay marina;  https://www.youtube.com/watch?v=bC0JYv_eM7k On several mornings the adults were very excited, or distressed, and swam in circles under the ‘Lighthouse’ and were seen leaping from the water. I later learned from the personnel from the vintage sailing ship ‘Vega’ that they had identified several very young pups in two dens; one under the ‘Lighthouse’ and another on the north-eastern corner of the marina. The latter den had access from the Marina and the open sea. The ‘Vega’ crew has rescued a young, ‘near-death’ pup and fed him back to health. The crew told me that the excited behaviour occurred at low-tides when the adults could not access the den under the lighthouse. Otters clearly had a need for tidal charts. The pups exacerbate the frenzy by being very vocal when hungry.

The 'Vega'.

Ariel view of Straits Quay marine showing the location of the two littering dens
Around the middle of January I did not hear the otters in the Marina any more although we had several sightings along the shoreline.

In the first and second weeks of February 2016 there were reports of around 6 otters denning in the barrier rocks along the promenade.  On the 12 and 13th of February I observed the denning in the afternoon from 3pm to 4pm. I was surprised to see 9-10 individual otters that caught fish with great ease and took them into the den. The majority of this group appears to be about the same size…….youngsters. Since the average litter size was three (also verified by the ‘Vega’ crew) the group had to consist of a crèche or an amalgamation of litters. I assumed that the two littering dens within the Straits Quay Marina was two different females and possibly the same male.















Denning Otters leave a localised odour and during this time I could identify several other odour hotspots along the rocks outside the marina. Otters were observed sprainting the rocks around their dens. The others in the group identify with this marking and sometime roll in the effluent as a bonding ritual. I have pointed out the odour to several friends and they had noticed it but blamed the nearby building site!



While making the observations of the Seri Tanjung Pinang otters there appeared to be a parallel story in Singapore with the Bishan Otters that had been in residence at a waterway in a park for several seasons. Similar to the Seri Tanjung Pinang group of 9 to 10 individuals there were 10 in the Bishan group. http://www.straitstimes.com/singapore/environment/bishan-5-now-bishan-10-with-new-otter-pups A nice video of the young pups swimming was shown posted recently https://www.youtube.com/watch?v=2co91sQ5igs. In the Bishan group the 5 new pups could have come from one litter or from perhaps two females. The timing of the birth of the litter(s) and the appearance of the pups is very similar the the STP group.

The STP group will later disperse as the pups gain maturity. During the rest of the year sightings will be less frequent and commonly only single otters or pairs will be sighted. At any time it is difficult to predict where the group will be....they clearly have multiple dens and from my experience will use a specific den for only two or three days before moving on.

Smooth-coated Otter numbers are diminishing and are listed as a threatened species. Their habitat is being destroyed and they face increasing competition for food supplies. Locally they compete with local fishermen and face danger when raiding the increasing numbers of fish farms. Sightings of these 'sea dogs' and their protection should be a privilege and a priority. Most residents are blase about the otters presence but there is a hard core of folk hoping to protect the group. We should all feel honoured that they choose to live amongst us.


Tuesday, 1 September 2015

Nesting behaviour of Red-throated Barbets

Depiction of Red-throated Barbets (female, at rear, is not correctly portrayed))

Barbets are included in the Order Picoformes which is made up of the woodpecker family Picidae plus 8 other families. It includes Puffbirds, Barbets, Toucans, Piculets and Woodpeckers. In general Picoformes are insectivorous but a minority eat mostly fruit. Nearly all Picoformes have parrot-like feet; two toes forward and two back, an arrangement that is advantageous for birds that spend most of their time on tree trunks. Picoformes do not have downy feathers at any stage with true feathers at all stages. All nest in cavities.

The related Common Flameback Woodpecker (male)

The related Common Flameback Woodpecker (female)

Battle of the Picoformes; A Lineated Barbet and a Streak-breasted
Woodpecker fight over a nest hole

Barbets consist of 83 species, 5 of which are threatened. are tropical birds originally designated in the family Capitodinae (see modification below). Barbets are named after the bristles at the base of their stout, sharp bills. They are big headed, short-tailed birds, 9-30cm (3.5-12 inches) long, greenish or brownish with splashes of bright colour or white. The smallest Barbets are known as tinkerbirds. The distribution of the family spans Central America, northern South America, sub-Saharan Africa and South-east Asia…. eastward to Borneo and to Bali. All species are non-migratory. Barbets sit solidly on treetops feeding on insects, lizards, birds’ eggs, fruit and berries. 


Related to Barbets the Collared Aracari, a Toucan from Costa Rica


Usambiro Barbet (an African Barbet species of the Lybiidae family)


Originally all Barbets were placed in the family Capitonidae but over time taxonomists have determined the family is more complex. The original Capitidonae (new World Barbets) with 14 species and Semnornithidae (Toucan Barbets) with 2 species (Toucans and Prong-billed Barbets). These American Barbets are more closely related to Toucans than they are to Barbets of other continents. In Asia 30 Barbet species are placed in their own family Megalaimidae and in Africa the 42 species are in the family Lybiidae.

Coppersmith Barbet

Coppersmith Barbet exiting nest hole

Coppersmith Barbet; removing the poop

Coppersmith Barbets; feeding the chick

RED-THROATED BARBETS

The Red-throated Barbets (syn Gaudy Barbets, German; Harlekinbartvogel; French; Barbu arlequin) as mentioned were previously classified as Megalaima mystacophanos but more recently as Psilopogon mystacophanos are found in Brunei, Indonesia, Malaysia, Myanmar, Singapore and Thailand. Its natural habitat is sub-tropical moist lowland forest and subtropical and tropical swamps. It is thought to be threatened by habitat loss but no numbers have been accurately recorded. The male has a red throat, yellow forehead, red crown, broad black eye line, blue cheeks and band across upper breast. The female has green head, red patches on lores, hind-crown and upper breast side. The breeding pair tends 2-4 white and glossy eggs in cavities with incubation time thought to be 13-15 days.

Distribution of the Red-throated Barbets

Male Red-throated Barbet

Male Red-throated Barbet
Female Red-throated barbet

The sound made is a single ‘tok’ or a series of 4 ‘toks’. A recording can be found here: http://www.xeno-canto.org/sounds/uploaded/EHGWCIGILC/XC173931-red-throated-barbet1.mp3

Red-throated Barbets are regarded by some observers as 'common' in certain forests but they are difficult to photograph except when nesting. I followed a nesting pair near Taiping during several morning sessions. 


Location of the nest hole (red circle)

It was interesting to compare it with the nesting of Coppersmith Barbets photographed earlier in the year. The Red-throated Barbet nesting seemed quite late in the year but my observation is that a nesting pair will base their nesting time on the availability of fruit and berries in the vicinity. In this case there was a fruiting tree 30 metres away and clearly others in the area. I had three visits essentially one week apart. On my first session the visits to the nest cavity was irregular with the male making most appearances with fruit. It was noticeable that the female was the only one that went into the nest to remove fecal material. Barbets are fastidious nest cleaners and earlier I had noted that faecal material was removed regularly from the Coppersmith Barbet nest. As the male and female look similar it was not possible to assign who was doing that task. On the first visit to the Red-throated Barbet nest no chicks were apparent peering from the nest entrance. 


Entering the small nest hole

Female bringing out the poop

A week later I counted 13 feedings from 7.45am until 11 am. The male fed the nest 10 of those times and the female 3 times but again she was the only one that went in to remove the poop. There were at least two chicks apparent in the nest with differences being noted as each peered from the entrance. One chick looked about 4 days more mature than the other …the latter showing a distinct colour forming. 


Male feeding the nest

Male with the more mature chick

Male with the more mature chick

On the third visit, 6 days later, there were 16 feedings in the same time frame and all were done by the male. The female did not make an appearance and consequently no poop was removed from the nest. The more mature chick had advanced in its colour and had a complete yellow forehead and generally smooth feathers with male colouration.  The other chick had developing colour and was possibly a female. It is interesting to note that in my identification book the chick is represented as having little or no adult colouration; which is clearly not the case. The chicks were fed with a lot of fruit and berries and the occasional insect.
As would be expected there are similarities between the nesting behaviour of Coppersmith Barbets and Red-throated barbets. Some years ago I also photographed the nesting of a pair of Lineated barbets and they too had similar patterns.


Male with the more mature chick

Male with the more mature chick

Male with the more mature chick

The more mature chick

The less mature chick

See 11c; chicks are incorrectly coloured in Robson's 'Birds of South-east Asia'

It seems that attempts to portray some species are not done with rigour. An internet search revealed that Barbets or various descriptions have been portrayed on the stamps of various countries. The Red-throated Barbet was portrayed on a stamp from the Maldives. The legend on the stamp however identified the portrayed bird as a Golden-throated Barbet. This listed species is shown from a bird identification book to be somewhat different from the bird on the stamp.

Red-throated Barbet portrayed on a stamp
but called a Golden-throated Barbet

Golden-throated Barbets are #3
While photographing the Barbets nesting there was other activity in the area. A troop of Pig-tailed Macaques passed through and Dusky Langurs dropped many metres from branch to branch in their foraging efforts. A young White-rumped Shama patrolled the bushes on the edge of the road and another species of Barbet, the Gold-whiskered barbet also plundered the fruiting tree. I was also surprised to see Blue-throated Bee-eaters in a nearby tree as they have long since departed the scene in another of my favourite locations.


Juvenile White-rumped Shama

Dusky Langur

Blue-throated Bee-eater

Gold-whiskered Barbet

Photographic Notes
The nest hole is well located on the side of a wide fairly quiet road. The road runs North/South and the sun rising in the east comes up behind the tree.....which is not ideal but later in the morning the ambient light is even and gets brighter as the sun traverses overhead. A long lens of 500-600mm with a converter is needed for the close detail. Of course this rig needs to be mounted on a sturdy tripod. I set my ISO from 1250 -1600 and was able to shoot at speeds from 1/400 to 1/1250 at my standard f8. the first day we waited in the heat for the sun to move until it was behind us. This did not work too well as the light became blotchy, which it often does in jungle conditions. 
It is most important to line up the background so it is relatively smooth....ie no white highlights. This often requires deft manoeuvring of the tripod as conditions change. The other thing to consider is the depth of the tree and positioning yourself so as much as possible of the wood surrounding the hole is also in focus. 
The nesting had attracted the attention of local photographers and many seemed obsessed with taking flight shots with the adult arriving or taking off. They would pump up the ISO on their cameras to any old value. I advocate determining what is the maximum ISO that you are comfortable with your camera....run a test. With my Canon 1DX is is 2000. I still need to run an anti-noise program for the background at this ISO. The other factor to consider is that for decent flight shots you need to be well over 1/2000th ideally......the faster the better. Unless the conditions are favourable i will not even attempt flight shots. I did see one reasonable flight shot from this nesting situation where a 600mm lens with a 1.4 converter was used and the ISO value lifted to 3200. The main advice here....know your equipment. 
Below is a previous shot of a nesting Lineated Barbet pair where the passage to the nest was open and lent itself to action shots.

Lineated Barbet feeding the nest

The Red-throated Barbet chicks fledged in the last few days of August 2015