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{{Taxobox
{{Taxobox
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| binomial_authority = ([[Wilhelm August Heinrich Blasius|Blasius]], 1896)
| binomial_authority = ([[Wilhelm August Heinrich Blasius|Blasius]], 1896)
}}
}}
=Storm’s Stork=
The '''Storm's stork''' (''Ciconia stormi'') is a large, approximately {{convert|91|cm|in}} long, [[stork]] with black and white plumages, red [[Beak|bill]], orange bare facial skin, red legs and yellow orbital skin. Both sexes are similar. The young has duller plumage and bare skin.
The '''Storm’s stork''' (''Ciconia stormi'') is a medium-sized stork species that occurs primarily in lowland tropical forests of [[Indonesia]], [[Malaysia]] and southern [[Thailand]]. It is considered to be the rarest of all storks<ref name="Hancocketal.">Hancock JA, Kuschlan JA, Kahl, MP. 1992. Storks, Ibises and Spoonbills of the World. Academic Press.</ref>, and is estimated to number less than 500 wild individuals throughout its geographic range<ref name="Birdlife International">Birdlife International. 2012. Ciconia Stormi. The IUCN Red List of Threatened Species 2012: e.T22697685A37859303. http://dx.doi.org/10.2305/IUCN.UK.20121.RLTS.T22697685A37859303.en</ref> . The population has long been in decline and the primary cause is widely considered to be deforestation of its native habitat<ref name="Birdlife International"/>.


This little known species is found in undisturbed forest and freshwater habitats in [[Sumatra]], [[Mentawai Islands]], [[Borneo]] and [[peninsular Malaysia]]. One of its strongholds are in southeast Sumatra, with remaining populations confined to [[Kalimantan]] and [[Brunei]]. While in peninsular Malaysia only one very small population and scattered individuals left. The world population of the Storm's stork is less than 500 individuals.


==Taxonomy and systematics==
The Storm's stork is a solitary bird. Its diet consists mainly of fish. The female usually lays two eggs in stick platform nest high in trees canopy.
This stork was first described by Blasius in 1896, and named after the German sea captain Hugo Storm, a collector of zoological specimens in the West Indies<ref name="Boelens et al.">Boelens B, Watkins M, Grayson M. 2014. The Eponym Dictionary of Birds. Bloomsbury, UK.</ref>. In Thailand, it is known as “nok kra su um”, which refers to the birds’ fishing procedure by stalking along the bank of a stream in dense forest<ref name="Nakhasathien">Nakhasathien S. 1987. The discovery of Storm’s stork Ciconia stormi in Thailand. Forktail 3:43-49.</ref>.

This species is very similar and closely related to the [[woolly-necked stork]]<ref name="Hancocketal."/> whose range partially overlaps with that of the Storm’s Stork<ref name="Holmes, 1977">Holmes DA. 1977. Faunistic notes and further additions to the Sumatran avifauna. Bulletin of the British Ornithologists’ Club. 97: 68-71.</ref>. Although the Storm’s stork has long been considered a separate species<ref>Chasen FN. 1935. Hand List of Malaysian Birds. Bulletin of Raffles Museum 11.</ref> <ref name="Hancock et al."/>, it has also been previously treated as a [[subspecies]] of the woolly-necked stork in the more recent past <ref name= "Kahl">Kahl MP. 1972. A revision of the Family Ciconiidae (Aves). Journal of Zoology 167: 451-461.</ref>. However, Storm’s stork is characterised by a yellowish-orange facial skin patch around the eye that is absent in the woolly-necked stork; and the neck is black and white, whereas it is completely white in the woolly-necked stork <ref name=''Hancocketal.''/>. However, the specific distinguishing features of Storm’s stork have been poorly known in the past, which in the field has frequently led to confusion with the woolly-necked stork <ref name="Holmes, 1977"/> <ref name ="Nakhasathien"/>.

These two species are also ecologically segregated, with the Storm’s stork keeping to dense forests and the woolly-necked stork mainly inhabiting open swamp, rice paddy, grassland and dry cultivated areas <ref name ="Nakhasathien"/>. There is evidence of [[sympatry]] of these two species in [[Sumatra]], where both of these habitats are present <ref name="Holmes, 1977"/>. Further, [[phylogenetic]] analyses of the Ciconiidae based on a portion of [[cytochrome oxidase]] b gene have suggested with strong support that the Storm’s stork and the woolly-necked stork are [[sister species]]<ref>Slikas B. 1997. Phylogeny of the avian family Ciconiidae (storks) based on cytochrome b sequences and DNA-DNA hybridisation distances. Molecular Phylogenetics and Evolution 8: 275-300.</ref>.
==Description==
This medium-sized stork stands at 75-91cm tall<ref name="Birdlife International"/>and most of the plumage is black. The undertail coverts and the back of neck are white with a black cap. It has orange facial skin with a yellow ring surrounding the eye, a red iris, and a pinkish-red bill. On some but not all male individuals, the [[culmen]] of the bill is slightly concave with a basal knob <ref name="oiseaux">oiseauxbirds.com. http://www.oiseaux-birds.com/card-storm-s-stork.html.Accessed 03/06/16</ref>.

The legs and feet of adults are dull red, but usually appear paler because they are often covered with the birds’ excreta <ref name="Hancocketal."/>. The bill and other soft body parts darken in the breeding season <ref name="Hancocketal."/>.The sexes are similar in appearance, but as in all storks, the male appears slightly larger. It is also speculated from field observations that the male’s black cap, chest and throat are slightly glossier<ref name="Hancocketal."/>.

The [[plumage]] of the chicks at 1-3 days old is completely white, accompanied by a black crown and a black bill with a yellow-orange tip <ref name="Hancocketal."/>. The legs, facial skin and [[gular pouch]] are initially light yellow; as the chicks age, the legs become pink, and the facial skin becomes dark grey. The iris is initially brown.

The chicks grow very fast, doubling in new-born size in just less than a month <ref name="Hancocketal."/>. By this time, they have also begun to develop black feathers on their wings, throats and bodies. After 30 days, the areas of black feathering have increased, and the black chest and wing coverts are streaked with glossy green and bronze-red <ref name="Nakhasathien"/>. After 45 days, the young resemble adults, but they are still smaller with shorter, dark-tipped bills and paler skin colourations, and the blackness of their plumage is slightly duller <ref name="oiseaux"/>. The chicks become fully feathered after 52-57 days <ref name="Danielsenetal.">Danielsen F. Kadarisman R, Skov H, Suwarman U, Verheugt WJM. 1997. The Storm’s stork Ciconia stormi in Indonesia: breeding biology population and conservation. Ibis 139: 67-75.</ref>.Wild young have been reported to leave the nest after about 60 days<ref name= "Nakhasathien"/>, and individuals in captivity can usually fly after 90 days<ref name="Nakhasathien"/>.
The adult birds are generally silent outside the breeding season; but during the breeding season they make vocalisations that may be described as “Kurau”<ref name="Smythies">Smythies BE. 1981. The Birds of Borneo, 3rd Edition. Malayan Nature Society, Kuala Lampur.</ref>. In captivity, one adult individual has been heard to make a quiet sibilant whistling<ref name="Hancocketal."/>. Chicks have been heard to make a relatively loud froglike [[begging call]] when parents return to the nest with food<ref name="Danielsenetal."/>.

==Distribution and habitat==
The majority of the world population lives throughout the island of [[Borneo]]; occurring in [[Kalimantan]] (Indonesia), [[Swarak]], [[Sabah]] (Malaysia) and [[Brunei]] <ref name ="Cutteretal.">Cutter P, Boontua P, Sri-Buarod K. 2007. A recent record of Storm’s Stork Ciconia stormi in Thailand. Forktail 23: 163-165</ref>. It is also found throughout Sumatra <ref name ="Birdlife International"/>, although its range there was previously considered to be restricted to the south east <ref name="Hancocketal."/>. Despite being widespread on both of these islands, the population occurs at low densities and only one or a few individuals have ever been sighted together <ref name="Hancocketal."/>, with the largest number being 12 during an observation in Brunei<ref>Holmes DA. 1969. Bird notes from Brunei: December 1967 – September 1968. Sarawak Museum Journal 17: 399-402.</ref>. Smaller numbers live in some parts of peninsular Malaysia, where it appears to be particularly rare <ref name="Luthin">Luthin CS. 1987. Status of and conservation priorities for the world’s stork species. Colonial Waterbirds 10: 181-202.</ref>. An even smaller minority lives in the extreme south of Thailand ref name="Birdlife International"/>, but this stork very unlikely occurs elsewhere in Thailand due to the near absence of remaining suitable habitat <ref name="Cutteretal."/>.

In 1986, the first nest of this species ever known to science was discovered in Southern Thailand < ref name="Nakhasathien"/>. However, the construction of the [[Chiew Larn Dam]] in the same year led to destruction of much of this stork’s lowland forest habitat through extensive flooding<ref name="Nakhasathien"/>. Following the flooding, Storm’s stork was therefore believed to no longer breed there<ref>Round P. 1988. Threatened forest birds of Thailand. ICBP Technical Publication Number 8. Cambridge: International Council for Bird Preservation.</ref> and since then was previously considered extinct in Thailand<ref>BirdLife International. 2001. Threatened birds of Asia: The Birdlife International Red Data Book. Cambridge, U.K.: BirdLife International.</ref>. However, this stork was re-sighted in Southern Thailand in 2004 with infrared camera traps<ref name="Cutteretal."/>; but continues to be exceptionally uncommon given that usually only one individual has been sighted at a time despite the high intensity of camera trapping <ref name="Cutteretal."/>. Nevertheless, its persistence in Southern Thailand does suggest the presence of a small breeding population <ref name="Cutteretal."/>.

This stork’s habitat is primarily dense lowland riverine forest and peat-swamp forest, at altitudes not exceeding 240 metres above sea level ref name="Danielsenetal."/>. The density of large trees in this habitat exceeding 10 cm at breast height is estimated to range from 500 to 800 trees per hectare< ref name="Nakhasathien"/>, and typical tree genera include ''[[Dipterocarpus]]'' and ''[[Ficus]]''<ref name="Nakhasathien"/>. The forest undergrowth predominantly comprises rattans, bamboos, shrubs and climbers <ref name="Nakhasathien"/>. Because these habitats are largely inaccessible to humans, collecting data on this species is logistically difficult <ref name="Danielsenetal."/>, which may partly explain why little is known about this stork’s natural history.

Although Storm’s stork accepts both lowland riverine forest and peat-swamp forest, it is currently unknown which of these habitats provide optimal living conditions for the species <ref name="Danielsenetal."/>. However, peat-swamp forest does appear to be an underestimated, ecologically important habitat for this stork across much of its range<ref name="Cheyneetal.">Cheyne SM, Husson SJ, Dragiew M, Thompson LJ, Adul, Jeffers KA, Limin SH, Smith DAE. 2014. Kalimantan’s tropical peat-swamp forests are important for Storm’s stork (Ciconia stormi) conservation. Journal of Indonesian Natural History 2: 45-50.</ref>. In the wake of continued anthropogenic loss of lowland riverine forest, peat-swamp forest possibly provides an important refuge for the species <ref name="Cheyneetal."/> and an extensive area of peat-swamp forest occurs in West Kalimantan<ref name="Roseetal.">Rose M, Posa C, Marques DA. 2012. Peat swamp forest birds of the Tuanan research station, Central Kalimantan, Indonesia, with notes on habitat specialists. Forktail 28:29-37.</ref>. However, this forest habitat is also under threat through conversion to palm oil plantations, logging and forest fires<ref name="Roseetal."/>, so that increased conservation efforts should be directed on protecting peat-swamp forest<ref name="Roseetal."/> .

This species has been shown to be somewhat tolerant of logged forests <ref name="Lambert">Lambert FR. 1992. The consequences of selective logging for Bornean lowland forest birds. Philosophical Transactions of the Royal Society of London 335: 443-457.</ref>; however, these areas’ actual value as a breeding habitat for this species is disputed <ref name="Lambert"/>. Danielsen and Heegaard <ref name="DanielsenandHeegaard">Danielsen F, Heegaard M. 1995. Impact of logging and plantation development on species diversity: a case study from Sumatra. In: Sandbukt Ø. 1995. Management of tropical forests: towards an integrated perspective. Olso: Centre for Development and the Environment, University of Oslo.</ref> have considered Storm’s stork incapable of breeding in logged forests despite apparent short term survival. In any case, current records have been too short to demonstrate long-term value of logged forests to this stork species <ref name="Berdie">Berdie IJ, 2008. Assessing canopy cover requirements of Storm’s Stork Ciconia stormi at multiple scales. Open access thesis. Paper 132.</ref>. The acceptance of logged forests by Storm’s stork may also entail some caveats; for example, that there must invariably be easy access within logged forest to freshwater margins <ref name="Berdie"/>, and that at least 20 years of forest regeneration should be allowed to elapse before real habitat value is re-established <ref name="Berdie"/>. A local mosaic of primary and logged forest may also explain this species’ apparent persistence in logged forest <ref name="DanielsenandHeegaard"/>, because it may rely on the undisturbed forest patches as a refuge to sustain itself in the logged forest patches <ref name="Lambert"/>.

This stork is often seen soaring at great heights over rivers and forest clearings, and like many other storks utilises thermal up-currents to assist it in gliding <ref name="Hancocketal."/>. This behaviour is said to be “contagious”<ref name="Hancocketal."/> because when one individual begins to soar, [[conspecifics]] join it in flight; with flocks consisting of up to six individuals <ref name="Hancocketal."/>.
On Borneo, it has also been reported on open, grassy freshwater swamps and paddy fields <ref name="Smythies"/>. It appears to never frequent saline habitats <ref name=Meijaardetal.">Meijaard E, Dennis R, Schroor P, Nardiyono, Berdie I, Douglas O, Fuller. 2015. Habitat characteristics of Storm’s stork Ciconiia stormi in Indonesian Borneo. Available at: https://www.researchgate.net/publication/272182067_Habitat_characteristics_of_Storm's_Stork_Ciconia_stormii_in_Indonesian_Borneo. Accessed 30/05/16.</ref>, but occasionally uses forested inland areas adjacent to bodies of water subject to tidal movements<ref name="Birdlife International"/> and near mangrove swamps <ref name="Meijaardetal."/>.

==Behaviour and ecology==
===Breeding===
Two major breeding records of this species have been made; in Southern Thailand in 1986 <ref name="Nakhasathien"/>, and in swamp forest in South Samatra in 1989 <ref name="Danielsenetal."/>. However, chicks in the Thailand breeding record were first observed in October <ref name="Nakhasathien"/> and those in Sumatra were first observed in early June <ref name="Danielsenetal."/>. The differing recorded times of egg laying in this species therefore does not suggest a strict breeding season. Collective breeding records of this species are currently scant possibly because nests are difficult to accurately locate in the dense forest habitat <ref name="Cheyneetal."/>.

The nest is usually located 19-30m above ground above riverbanks, often in the forks of trees of ''[[Dipterocarpus]]'' species <ref name="Nakhasathien"/>. At south Sumatra, a Storm’s stork nest was studied that lay 8.3m above ground in an 18m-tall ''[[Rhizosphora mucronata]]'' tree<ref name="Danielsenetal."/>. In captivity, both the male and female have been observed to carry out nest-building activities<ref name ="Maceetal.">Mace M, Ranger W, Lewins E, Atallian DM, Farley M. 2006. Breeding and hand-rearing Storm’s storks Ciconia stormi at the Zoological Society of San Diego. International Zoo Yearbook 40: 254-260.</ref>. The nest has an external outer diameter measuring between 30 and 50 cm <ref name="Nakhasathien"/><ref name="Danielsenetal./>;with a depth of 10-15cm <ref name="Nakhasathien"/><ref name="Danielsenetal./>, and is typically composed of twigs and sticks mainly belonging to tree species in the ''Rhizosphora'' genus <ref name="Danielsenetal."/>, but also from species in the families Loranthaceae, Dipterocarpaceae, and Rubinaceae <ref name="Nakhasathien"/>. These sticks measure 15- 60cm in length <ref name="Nakhasathien"/><ref name="Danielsenetal."/><ref name="Maceetal."/> and 0.5-1.5cm in diameter<ref name="Danielsenetal."/><ref name="Maceetal."/>. The nest interior is lined with soft material such as grass and down. 2-4 cm long leaflets from "Xylocarpus" species have also been identified as nest material<ref name="Danielsenetal."/>, and these plants have been found growing in the area surrounding the nest <ref name="Danielsenetal."/>. The same nest is often used by a pair over consecutive years; whereby both mates add more material to the nest each year <ref name="oiseaux"/>.

Male-female pairs of this species are typically monogamous <ref name="oiseaux"/>. Both parents attend to the young at the nest, but only one parent at a time is usually present; with the female estimated to spend three times as long alone at the nest as the male <ref name="Danielsenetal."/> . In the early stages of the chicks’ life, both parents have been observed to roost at or near the nest during the evening; but within a month only the female continues to roost at or near the nest <ref name="Danielsenetal."/>. Contrary to previous assertions<ref>MacKinnon J. Phillips K. 1993. A Field Guide to the Birds of Borneo, Sumatra, Java, and Bali. Oxford: Oxford University Press.</ref>,this species actually appears to breed solitarily and does not nest in colonies <ref name="Danielsenetal."/>. However, it is sometimes found to roost communally, and several individuals have been observed roosting in tops of tall swamp trees a few kilometres from the nests <ref name="Danielsenetal."/>.

Two eggs are usually laid per year <ref name="Birdlife International"/>, and the [[incubation]] period has been estimated at 29 days <ref name="Danielsenetal."/>, with both parents alternately incubating the eggs <ref name="Maceetal."/>. In captivity, the clutch size may range between two and four <ref name="Maceetal."/>.The young are fully fledged 90 days after hatching <ref name="Birdlife Interational"/>. The only egg of this species to have been measured was an infertile one extracted from a nest containing two hatched chicks in south Sumatra in 1989<ref name="Danielsenetal."/>.This egg measured 60.1mm in length and 41.9mm in breadth, and was completely white after cleaning <ref name="Danielsenetal."/> .This egg is preserved at the [[Zoological Museum of Bogor]], Indonesia, and is currently the only egg specimen available for this species <ref name="Danielsenetal."/>.

Pairs of this stork species perform impressive aerial [[courtship displays]] in which both partners do flips in flight, with the lower birds presenting its feet to the upper. Both birds also occasionally glide at high altitudes with level wings and dangling legs <ref name="Meijaardetal."/>. At the nest, they perform bill clattering activities that are typical of many species in the [[Ciconiidae]] (Kahl, 1972; http://www.oiseaux-birds.com/card-storm-s-stork.html).

In captivity, another courtship display has been observed in which both partners face each other on the ground or on the nest, extend their wings outward from the body, and bow to each other repeatedly. This display continues until the male approaches the female and attempts to copulate with her <ref name="Maceetal."/>, although copulation does not actually follow from most such displays. This display also sometimes continues when breeding is finished and chicks are at the nest <ref name="Maceetal."/>. However, the importance of this display in wild populations is unknown, since both parents have been sighted together at the nest for only 2% of the time from observations<ref="Danielsenetal."/>.
===Food and feeding===
The Storm’s stork feeds primarily on small fish, frogs, aquatic insect larvae, and sometimes earthworms <ref name="Danielsenetal."/>.These are also the food items brought by both parents back for their young at the nest; with the fish measuring 5-7cm long and weighing 10-30g, and the worms measuring 10-15cm long <ref name="Hancocketal."/>. The parents regurgitate the food into the bottom of the nest, whereupon it is picked up and swallowed by the chicks<ref name="Danielsenetal."/>. During a series of nest observations in south Sumatra in 1989, adults were found to return to the nest with food for the chicks every 2-4 hours in June,; but in July, food was brought to the nest less often and significantly more frequently in the late afternoons<ref name="Danielsenetal."/>. In Sabah, they have also been reported to feed on grasshoppers and possibly crabs<ref name="Meijaardetal."/>. Hence, other food taxa may be similar to those of the woollynecked stork, but more data are required to fully confirm this ,<ref name="Hancocketal."/>.

This stork typically forages stealthily with slow, deliberate movements and a retracted neck <ref (Meijaard et al.,2014) along muddy banks of rivers and creeks within dense primary forest(Hancock et al. 1992; Danielsen et al. , 1997); keeping primarily to the shaded areas (Berdie, 2008). Individuals with chicks usually forage 2-3km from the nest (Danielsen et al. 1997). It will also use other freshwater bodies as foraging localities with high densities of fish and freshwater invertebrates (Berdie, 2008). These include small pools, trackside puddles, swamps and oxbow lakes (Berdie, 2008); and the Storm’s stork may be able to use these features optimally where they occur in a patchwork arrangement on riparian floodplains (Berdie, 2008). It can also use boggy clearings created by ungulates such as gaus that trample vegetation to access mineral licks (Meijaard et al., 2014). In contrast, deep, fast-flowing rivers and waterways are avoided by this species due to reduced prey availability and its inability to stand in these waters (Berdie, 2008).

In Sabah, they have been found feeding on open ground that has recently been burnt (Meijaard, 2014). They probably catch invertebrates that have been disturbed or killed by the fire (Meijaard et al. 2014).

===Threats and survival===
The primary threat to this species is degradation of its lowland forest habitat through deforestation for logging and conversion to oil palm plantations (Hancock et al., 1992; Danielsen et al., 1997; Birdlife International, 2012). For example, approximately two thirds of the swamp forests in South Sumatra were logged from 1982 to 1997 (Danielsen et al., 1997). Kalimantan lost almost 25% of its evergreen forest during 1985-1997 and all of Sumatra almost 30% of its 1985 cover (Birdlife International, 2012). The relative extent of destruction of this species’ habitat may be particularly high because clearance of lowland forests typically occurs first in deforestation schemes due to the relative ease of approach and the presence of high quality timber (Dinata et al. 2008). Extensive habitat destruction has also occurred through flooding of lowland forest following the construction of reservoirs, as epitomised by the Chiew Larn Dam project in Southern Thailand (Nakashien, 1987). Because this stork is a lowland specialist (Danielsen et al., 1997), high-elevation forest remaining intact after destruction and fragmentation of lowland habitat is unsuitable, so that transmigration to higher altitude forests is unlikely to be a viable escape solution (Nakahasien 1987).

The Storm’s stork is possibly not strongly directly affected by habitat fragmentation through deforestation (Berdie, 2008). It may actually be somewhat tolerant of fragmentation because it could fly great distances in search of new habitat and be relatively unaffected by the open land matrix which it overflies (Berdie, 2008). However, this is probably not a favourable situation for the species, and the exact maximum distances it will travel to reach new habitat are currently unknown (Berdie 2008). A larger impact of deforestation on the Storm’s stork is more likely to be the decrease in freshwater faunal prey abundance and diversity resulting from increased sedimentation, nutrient loads and water temperatures after logging (Danielsen et al., 1997; Hardin et al. 2003). This loss of freshwater taxa would in turn decrease food availability for this stork at its foraging sites (Berdie, 2008). Road building through the forests to access logging areas creates similar problems by contributing to soil erosion, thereby also decreasing freshwater prey diversity (Danielsen et al., 1997). The large canopy gaps created through logging also lead to drier abiotic conditions in the cleared areas than under dense canopy, which would render these areas unsuitable for food taxa of the Storm’s stork such as amphibians and invertebrates that require wet substrates to live on (Berdie, 2008). This is another likely contributor to the decrease in food taxa abundance after forest clearing.

A secondary threat to this species is hunting by humans (Nakhashien, 1987; Hancock et al.,1992; Danielson et al., 1997). Hunting of this species by local people for food may have been happening before large-scale human encroachment onto its habitat to exploit the land (Nakaashien, 1987). However, extensive land exploitation increases human activities that attract non-native hunters to these areas, so that hunting of this species through direct persecution has also appeared to increase as a side-effect of the direct impacts of habitat destruction (Hancock et al., 1992). This was probably the case during extensive flooding of lowland forest in Southern Thailand during the Chiew Larn Dam project (Nakahasien, 1987).
This species is also extremely sensitive to human intrusions. If humans come within sight of the nest, the adult abandons the nest and does not return until 2-3 hours after the intruder departs (Danielsen et al., 1997). Anthropogenic noise sources such as from motorboats and chainsaws may also affect this stork; in response to such noises that penetrate the forest matrix, adult birds have been observed to press their head and body into the nest with only the eyes showing (Danielsen et al. ,1997).

Natural enemies of chicks and nesting adults are believed to include raptors such as crested serpent eagles Spilornis cheela, monkeys and corvids (Hancock et al., 1992). If these organisms approach the nest, the parent spreads its wings over the nestlings to protect them (Hancock et al. 1992). This nest covering display is similar to that observed in the Magauri stork ( Kahl, 1972).

Another minor threat is the capture of individuals for the international zoo trade, which increased markedly in the late 1980s (Hancock et al., 1992). Although captivity of Storm’s storks may be a solution to support the global population, these birds may be unsuitable to reintroduce to their natural habitat because they have become too tame (Nakashien, 1987). In Singapore, the price of this species on bird markets doubled ($300 to $600) in the early 1990s (Hancock et al., 1992). However, there is no evidence that they have international trade value (Danielsen et al., 1997).
==Relationship to humans==
This stork is sometimes hunted for food, either by native forest dwellers or non-natives who have been attracted to the area by large-scale land exploitation projects<ref name="Hancocketal."/>. Although there is a relatively low human population density in areas of undisturbed forest habitat of this species, these people concentrate on gleaning forest products and poaching wildlife. During these activities, Storm’s storks are occasionally caught for food either directly by people who extract latex from the [[jelutong]] tree, or in baited traps for the monitor lizard ''[[Varanus serator]]''<ref name="Danielsenetal."/>.

Individuals of this species have appeared in many zoological institutions such as in Kuala Lumpur in Malaysia and [[Walsrode]] in [[Germany]]<ref name="Hancocketal"/>. However, the only two zoos where this species has successfully bred are Zoo Negara, Malaysia; and San Diego Wild Animal Park, California<ref name="Maceetal."/>.
==Status==
The population of this notably rare species has been thought to be in recent rapid decline, primarily due to clearance of its natural habitat to make way for oil palm plantations and logging activities <ref name="Birdlife International"/>. It has probably never been common, even before extensive habitat destruction from increased anthropogenic land exploitation<ref name="Nakhasathien"/><ref name="Luthin"/>.

It has been classified as Endangered on the [[IUCN Red List]] since 1994 <ref name="Birdlife International"/>. The total population has been estimated to number 400-500 wild individuals<ref name="Birdlife International"/>. Of these individuals, 150 are estimated to live in Malaysia; and an estimated 250 in Indonesia <ref name="Birdlife International"/>. This species is legally protected in Indonesia, Sarawak and Thailand<ref name="Birdlife International"/>. Although such protection has previously not been rigorously enforced<ref name="Hancocketal."/>, this stork has been recorded in numerous protected areas throughout its range, especially in Kalimantan, on Sumatra and in Malaysia<ref name="Birdlife International"/> .

This species requires extensive areas of dense lowland forest over which to forage<ref name="Berdie"/>, so that the best solution to protect this species from extinction would be the large-scale establishment of protected areas holding undisturbed lowland forest and riparian features<ref name="Hancocketal."/>. However, because this stork is very secretive, it has proved difficult to investigate its biology and ecology. Although it is almost certainly negatively affected by deforestation, little continues to be known about the exact extent of its responses to anthropogenic changes in its native habitat<ref name="Berdie"/>.



The Storm's stork was formerly considered as a subspecies of the [[woolly-necked stork]].


Due to ongoing habitat loss, very small population size, limited range and overhunting in some areas, the Storm's stork is classified as [[Endangered]] on the [[IUCN Red List of Threatened Species]].


==Gallery==
==Gallery==
Line 32: Line 103:
Image:Storm's Stork SMTC2.jpg|At [[San Diego Zoo]]
Image:Storm's Stork SMTC2.jpg|At [[San Diego Zoo]]
</gallery>
</gallery>

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== References ==
{{reflist}}


==External links==
==External links==
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{{Ciconiiformes-stub}}
{{Ciconiiformes-stub}}
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==References==
<ref>references</ref>

Revision as of 14:58, 3 June 2016

Storm's stork
At San Diego Zoo
Scientific classification
Kingdom:
Animalia
Phylum:
Chordata
Class:
Aves
Order:
Ciconiiformes
Family:
Ciconiidae
Genus:
Ciconia
Species:
C. stormi
Binomial name
Ciconia stormi
(Blasius, 1896)

Storm’s Stork

The Storm’s stork (Ciconia stormi) is a medium-sized stork species that occurs primarily in lowland tropical forests of Indonesia, Malaysia and southern Thailand. It is considered to be the rarest of all storks[2], and is estimated to number less than 500 wild individuals throughout its geographic range[3] . The population has long been in decline and the primary cause is widely considered to be deforestation of its native habitat[3].


Taxonomy and systematics

This stork was first described by Blasius in 1896, and named after the German sea captain Hugo Storm, a collector of zoological specimens in the West Indies[4]. In Thailand, it is known as “nok kra su um”, which refers to the birds’ fishing procedure by stalking along the bank of a stream in dense forest[5].

This species is very similar and closely related to the woolly-necked stork[2] whose range partially overlaps with that of the Storm’s Stork[6]. Although the Storm’s stork has long been considered a separate species[7] [8], it has also been previously treated as a subspecies of the woolly-necked stork in the more recent past [9]. However, Storm’s stork is characterised by a yellowish-orange facial skin patch around the eye that is absent in the woolly-necked stork; and the neck is black and white, whereas it is completely white in the woolly-necked stork Cite error: The opening <ref> tag is malformed or has a bad name (see the help page).. However, the specific distinguishing features of Storm’s stork have been poorly known in the past, which in the field has frequently led to confusion with the woolly-necked stork [6] [5].

These two species are also ecologically segregated, with the Storm’s stork keeping to dense forests and the woolly-necked stork mainly inhabiting open swamp, rice paddy, grassland and dry cultivated areas [5]. There is evidence of sympatry of these two species in Sumatra, where both of these habitats are present [6]. Further, phylogenetic analyses of the Ciconiidae based on a portion of cytochrome oxidase b gene have suggested with strong support that the Storm’s stork and the woolly-necked stork are sister species[10].

Description

This medium-sized stork stands at 75-91cm tall[3]and most of the plumage is black. The undertail coverts and the back of neck are white with a black cap. It has orange facial skin with a yellow ring surrounding the eye, a red iris, and a pinkish-red bill. On some but not all male individuals, the culmen of the bill is slightly concave with a basal knob [11].

The legs and feet of adults are dull red, but usually appear paler because they are often covered with the birds’ excreta [2]. The bill and other soft body parts darken in the breeding season [2].The sexes are similar in appearance, but as in all storks, the male appears slightly larger. It is also speculated from field observations that the male’s black cap, chest and throat are slightly glossier[2].

The plumage of the chicks at 1-3 days old is completely white, accompanied by a black crown and a black bill with a yellow-orange tip [2]. The legs, facial skin and gular pouch are initially light yellow; as the chicks age, the legs become pink, and the facial skin becomes dark grey. The iris is initially brown.

The chicks grow very fast, doubling in new-born size in just less than a month [2]. By this time, they have also begun to develop black feathers on their wings, throats and bodies. After 30 days, the areas of black feathering have increased, and the black chest and wing coverts are streaked with glossy green and bronze-red [5]. After 45 days, the young resemble adults, but they are still smaller with shorter, dark-tipped bills and paler skin colourations, and the blackness of their plumage is slightly duller [11]. The chicks become fully feathered after 52-57 days [12].Wild young have been reported to leave the nest after about 60 days[5], and individuals in captivity can usually fly after 90 days[5].

The adult birds are generally silent outside the breeding season; but during the breeding season they make vocalisations that may be described as “Kurau”[13]. In captivity, one adult individual has been heard to make a quiet sibilant whistling[2]. Chicks have been heard to make a relatively loud froglike begging call when parents return to the nest with food[12].

Distribution and habitat

The majority of the world population lives throughout the island of Borneo; occurring in Kalimantan (Indonesia), Swarak, Sabah (Malaysia) and Brunei [14]. It is also found throughout Sumatra [3], although its range there was previously considered to be restricted to the south east [2]. Despite being widespread on both of these islands, the population occurs at low densities and only one or a few individuals have ever been sighted together [2], with the largest number being 12 during an observation in Brunei[15]. Smaller numbers live in some parts of peninsular Malaysia, where it appears to be particularly rare [16]. An even smaller minority lives in the extreme south of Thailand ref name="Birdlife International"/>, but this stork very unlikely occurs elsewhere in Thailand due to the near absence of remaining suitable habitat [14].

In 1986, the first nest of this species ever known to science was discovered in Southern Thailand < ref name="Nakhasathien"/>. However, the construction of the Chiew Larn Dam in the same year led to destruction of much of this stork’s lowland forest habitat through extensive flooding[5]. Following the flooding, Storm’s stork was therefore believed to no longer breed there[17] and since then was previously considered extinct in Thailand[18]. However, this stork was re-sighted in Southern Thailand in 2004 with infrared camera traps[14]; but continues to be exceptionally uncommon given that usually only one individual has been sighted at a time despite the high intensity of camera trapping [14]. Nevertheless, its persistence in Southern Thailand does suggest the presence of a small breeding population [14].

This stork’s habitat is primarily dense lowland riverine forest and peat-swamp forest, at altitudes not exceeding 240 metres above sea level ref name="Danielsenetal."/>. The density of large trees in this habitat exceeding 10 cm at breast height is estimated to range from 500 to 800 trees per hectare< ref name="Nakhasathien"/>, and typical tree genera include Dipterocarpus and Ficus[5]. The forest undergrowth predominantly comprises rattans, bamboos, shrubs and climbers [5]. Because these habitats are largely inaccessible to humans, collecting data on this species is logistically difficult [12], which may partly explain why little is known about this stork’s natural history.

Although Storm’s stork accepts both lowland riverine forest and peat-swamp forest, it is currently unknown which of these habitats provide optimal living conditions for the species [12]. However, peat-swamp forest does appear to be an underestimated, ecologically important habitat for this stork across much of its range[19]. In the wake of continued anthropogenic loss of lowland riverine forest, peat-swamp forest possibly provides an important refuge for the species [19] and an extensive area of peat-swamp forest occurs in West Kalimantan[20]. However, this forest habitat is also under threat through conversion to palm oil plantations, logging and forest fires[20], so that increased conservation efforts should be directed on protecting peat-swamp forest[20] .

This species has been shown to be somewhat tolerant of logged forests [21]; however, these areas’ actual value as a breeding habitat for this species is disputed [21]. Danielsen and Heegaard [22] have considered Storm’s stork incapable of breeding in logged forests despite apparent short term survival. In any case, current records have been too short to demonstrate long-term value of logged forests to this stork species [23]. The acceptance of logged forests by Storm’s stork may also entail some caveats; for example, that there must invariably be easy access within logged forest to freshwater margins [23], and that at least 20 years of forest regeneration should be allowed to elapse before real habitat value is re-established [23]. A local mosaic of primary and logged forest may also explain this species’ apparent persistence in logged forest [22], because it may rely on the undisturbed forest patches as a refuge to sustain itself in the logged forest patches [21].

This stork is often seen soaring at great heights over rivers and forest clearings, and like many other storks utilises thermal up-currents to assist it in gliding [2]. This behaviour is said to be “contagious”[2] because when one individual begins to soar, conspecifics join it in flight; with flocks consisting of up to six individuals [2]. On Borneo, it has also been reported on open, grassy freshwater swamps and paddy fields [13]. It appears to never frequent saline habitats [24], but occasionally uses forested inland areas adjacent to bodies of water subject to tidal movements[3] and near mangrove swamps [25].

Behaviour and ecology

Breeding

Two major breeding records of this species have been made; in Southern Thailand in 1986 [5], and in swamp forest in South Samatra in 1989 [12]. However, chicks in the Thailand breeding record were first observed in October [5] and those in Sumatra were first observed in early June [12]. The differing recorded times of egg laying in this species therefore does not suggest a strict breeding season. Collective breeding records of this species are currently scant possibly because nests are difficult to accurately locate in the dense forest habitat [19].

The nest is usually located 19-30m above ground above riverbanks, often in the forks of trees of Dipterocarpus species [5]. At south Sumatra, a Storm’s stork nest was studied that lay 8.3m above ground in an 18m-tall Rhizosphora mucronata tree[12]. In captivity, both the male and female have been observed to carry out nest-building activities[26]. The nest has an external outer diameter measuring between 30 and 50 cm [5][12];with a depth of 10-15cm [5][12], and is typically composed of twigs and sticks mainly belonging to tree species in the Rhizosphora genus [12], but also from species in the families Loranthaceae, Dipterocarpaceae, and Rubinaceae [5]. These sticks measure 15- 60cm in length [5][12][26] and 0.5-1.5cm in diameter[12][26]. The nest interior is lined with soft material such as grass and down. 2-4 cm long leaflets from "Xylocarpus" species have also been identified as nest material[12], and these plants have been found growing in the area surrounding the nest [12]. The same nest is often used by a pair over consecutive years; whereby both mates add more material to the nest each year [11].

Male-female pairs of this species are typically monogamous [11]. Both parents attend to the young at the nest, but only one parent at a time is usually present; with the female estimated to spend three times as long alone at the nest as the male [12] . In the early stages of the chicks’ life, both parents have been observed to roost at or near the nest during the evening; but within a month only the female continues to roost at or near the nest [12]. Contrary to previous assertions[27],this species actually appears to breed solitarily and does not nest in colonies [12]. However, it is sometimes found to roost communally, and several individuals have been observed roosting in tops of tall swamp trees a few kilometres from the nests [12].

Two eggs are usually laid per year [3], and the incubation period has been estimated at 29 days [12], with both parents alternately incubating the eggs [26]. In captivity, the clutch size may range between two and four [26].The young are fully fledged 90 days after hatching [28]. The only egg of this species to have been measured was an infertile one extracted from a nest containing two hatched chicks in south Sumatra in 1989[12].This egg measured 60.1mm in length and 41.9mm in breadth, and was completely white after cleaning [12] .This egg is preserved at the Zoological Museum of Bogor, Indonesia, and is currently the only egg specimen available for this species [12].

Pairs of this stork species perform impressive aerial courtship displays in which both partners do flips in flight, with the lower birds presenting its feet to the upper. Both birds also occasionally glide at high altitudes with level wings and dangling legs [25]. At the nest, they perform bill clattering activities that are typical of many species in the Ciconiidae (Kahl, 1972; http://www.oiseaux-birds.com/card-storm-s-stork.html).

In captivity, another courtship display has been observed in which both partners face each other on the ground or on the nest, extend their wings outward from the body, and bow to each other repeatedly. This display continues until the male approaches the female and attempts to copulate with her [26], although copulation does not actually follow from most such displays. This display also sometimes continues when breeding is finished and chicks are at the nest [26]. However, the importance of this display in wild populations is unknown, since both parents have been sighted together at the nest for only 2% of the time from observations<ref="Danielsenetal."/>.

Food and feeding

The Storm’s stork feeds primarily on small fish, frogs, aquatic insect larvae, and sometimes earthworms [12].These are also the food items brought by both parents back for their young at the nest; with the fish measuring 5-7cm long and weighing 10-30g, and the worms measuring 10-15cm long [2]. The parents regurgitate the food into the bottom of the nest, whereupon it is picked up and swallowed by the chicks[12]. During a series of nest observations in south Sumatra in 1989, adults were found to return to the nest with food for the chicks every 2-4 hours in June,; but in July, food was brought to the nest less often and significantly more frequently in the late afternoons[12]. In Sabah, they have also been reported to feed on grasshoppers and possibly crabs[25]. Hence, other food taxa may be similar to those of the woollynecked stork, but more data are required to fully confirm this ,[2].

This stork typically forages stealthily with slow, deliberate movements and a retracted neck Cite error: The <ref> tag has too many names (see the help page).. Although there is a relatively low human population density in areas of undisturbed forest habitat of this species, these people concentrate on gleaning forest products and poaching wildlife. During these activities, Storm’s storks are occasionally caught for food either directly by people who extract latex from the jelutong tree, or in baited traps for the monitor lizard Varanus serator[12].

Individuals of this species have appeared in many zoological institutions such as in Kuala Lumpur in Malaysia and Walsrode in Germany[29]. However, the only two zoos where this species has successfully bred are Zoo Negara, Malaysia; and San Diego Wild Animal Park, California[26].

Status

The population of this notably rare species has been thought to be in recent rapid decline, primarily due to clearance of its natural habitat to make way for oil palm plantations and logging activities [3]. It has probably never been common, even before extensive habitat destruction from increased anthropogenic land exploitation[5][16].

It has been classified as Endangered on the IUCN Red List since 1994 [3]. The total population has been estimated to number 400-500 wild individuals[3]. Of these individuals, 150 are estimated to live in Malaysia; and an estimated 250 in Indonesia [3]. This species is legally protected in Indonesia, Sarawak and Thailand[3]. Although such protection has previously not been rigorously enforced[2], this stork has been recorded in numerous protected areas throughout its range, especially in Kalimantan, on Sumatra and in Malaysia[3] .

This species requires extensive areas of dense lowland forest over which to forage[23], so that the best solution to protect this species from extinction would be the large-scale establishment of protected areas holding undisturbed lowland forest and riparian features[2]. However, because this stork is very secretive, it has proved difficult to investigate its biology and ecology. Although it is almost certainly negatively affected by deforestation, little continues to be known about the exact extent of its responses to anthropogenic changes in its native habitat[23].



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References

[30]

  1. ^ Template:IUCN
  2. ^ a b c d e f g h i j k l m n o p q Hancock JA, Kuschlan JA, Kahl, MP. 1992. Storks, Ibises and Spoonbills of the World. Academic Press.
  3. ^ a b c d e f g h i j k l Birdlife International. 2012. Ciconia Stormi. The IUCN Red List of Threatened Species 2012: e.T22697685A37859303. http://dx.doi.org/10.2305/IUCN.UK.20121.RLTS.T22697685A37859303.en
  4. ^ Boelens B, Watkins M, Grayson M. 2014. The Eponym Dictionary of Birds. Bloomsbury, UK.
  5. ^ a b c d e f g h i j k l m n o p q Nakhasathien S. 1987. The discovery of Storm’s stork Ciconia stormi in Thailand. Forktail 3:43-49.
  6. ^ a b c Holmes DA. 1977. Faunistic notes and further additions to the Sumatran avifauna. Bulletin of the British Ornithologists’ Club. 97: 68-71.
  7. ^ Chasen FN. 1935. Hand List of Malaysian Birds. Bulletin of Raffles Museum 11.
  8. ^ Cite error: The named reference Hancock et al. was invoked but never defined (see the help page).
  9. ^ Kahl MP. 1972. A revision of the Family Ciconiidae (Aves). Journal of Zoology 167: 451-461.
  10. ^ Slikas B. 1997. Phylogeny of the avian family Ciconiidae (storks) based on cytochrome b sequences and DNA-DNA hybridisation distances. Molecular Phylogenetics and Evolution 8: 275-300.
  11. ^ a b c d oiseauxbirds.com. http://www.oiseaux-birds.com/card-storm-s-stork.html.Accessed 03/06/16
  12. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z Danielsen F. Kadarisman R, Skov H, Suwarman U, Verheugt WJM. 1997. The Storm’s stork Ciconia stormi in Indonesia: breeding biology population and conservation. Ibis 139: 67-75.
  13. ^ a b Smythies BE. 1981. The Birds of Borneo, 3rd Edition. Malayan Nature Society, Kuala Lampur.
  14. ^ a b c d e Cutter P, Boontua P, Sri-Buarod K. 2007. A recent record of Storm’s Stork Ciconia stormi in Thailand. Forktail 23: 163-165
  15. ^ Holmes DA. 1969. Bird notes from Brunei: December 1967 – September 1968. Sarawak Museum Journal 17: 399-402.
  16. ^ a b Luthin CS. 1987. Status of and conservation priorities for the world’s stork species. Colonial Waterbirds 10: 181-202.
  17. ^ Round P. 1988. Threatened forest birds of Thailand. ICBP Technical Publication Number 8. Cambridge: International Council for Bird Preservation.
  18. ^ BirdLife International. 2001. Threatened birds of Asia: The Birdlife International Red Data Book. Cambridge, U.K.: BirdLife International.
  19. ^ a b c Cheyne SM, Husson SJ, Dragiew M, Thompson LJ, Adul, Jeffers KA, Limin SH, Smith DAE. 2014. Kalimantan’s tropical peat-swamp forests are important for Storm’s stork (Ciconia stormi) conservation. Journal of Indonesian Natural History 2: 45-50.
  20. ^ a b c Rose M, Posa C, Marques DA. 2012. Peat swamp forest birds of the Tuanan research station, Central Kalimantan, Indonesia, with notes on habitat specialists. Forktail 28:29-37.
  21. ^ a b c Lambert FR. 1992. The consequences of selective logging for Bornean lowland forest birds. Philosophical Transactions of the Royal Society of London 335: 443-457.
  22. ^ a b Danielsen F, Heegaard M. 1995. Impact of logging and plantation development on species diversity: a case study from Sumatra. In: Sandbukt Ø. 1995. Management of tropical forests: towards an integrated perspective. Olso: Centre for Development and the Environment, University of Oslo.
  23. ^ a b c d e Berdie IJ, 2008. Assessing canopy cover requirements of Storm’s Stork Ciconia stormi at multiple scales. Open access thesis. Paper 132.
  24. ^ Meijaard E, Dennis R, Schroor P, Nardiyono, Berdie I, Douglas O, Fuller. 2015. Habitat characteristics of Storm’s stork Ciconiia stormi in Indonesian Borneo. Available at: https://www.researchgate.net/publication/272182067_Habitat_characteristics_of_Storm's_Stork_Ciconia_stormii_in_Indonesian_Borneo. Accessed 30/05/16.
  25. ^ a b c Cite error: The named reference Meijaardetal. was invoked but never defined (see the help page).
  26. ^ a b c d e f g h Mace M, Ranger W, Lewins E, Atallian DM, Farley M. 2006. Breeding and hand-rearing Storm’s storks Ciconia stormi at the Zoological Society of San Diego. International Zoo Yearbook 40: 254-260.
  27. ^ MacKinnon J. Phillips K. 1993. A Field Guide to the Birds of Borneo, Sumatra, Java, and Bali. Oxford: Oxford University Press.
  28. ^ Cite error: The named reference Birdlife Interational was invoked but never defined (see the help page).
  29. ^ Cite error: The named reference Hancocketal was invoked but never defined (see the help page).
  30. ^ references
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