del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.
Red List criteria met
Red List history
IUCN Red List criteria met and history
||does not normally occur in forest
Population justification: The population is estimated at 2,450-2,900 mature individuals, based on the compilation of counts and expert estimates from across the species's range (Chowdhury et al. 2020, Shaikh 2020, S.U. Chowdhury, D.K. Das, S. Debata, S. Mohsanin, T. Munkur, P. Shaikh, C Zöckler in litt. 2020). Much of the research into the status of the species was collated during the Riverine birds of the Central Asian Flyway workshop in November 2019.
The revised estimate is based on numbers recorded during the non-breeding season, when a majority of the population occurs in a few large groups at regular sites. The largest numbers recorded in recent decades have been from the Meghna-Padma delta in Bangladesh, where a total of 3,108 individuals were counted at Nijhum Dwip in February 2020 (D.K. Das in litt. 2020). This is the highest count since 2001, when 5,400 individuals were recorded from the same area (Li et al. 2009). This 2020 count is considerably higher than the previous counts conducted in the area in the 2019/20 season (and for many years), it presumably includes birds noted earlier from Chittagong (Chowdhury et al. 2020) plus any wintering birds unseen in the area. As such it is likely to represent a count close to the total number wintering in Bangladesh.
In India, most observations during the non-breeding season are of few birds but larger congregations are known from a handful of key sites. To the far west of the range c. 150 are regularly recorded from Jamnagar in Gujarat (eBird 2020, Shaikh 2020), centrally c. 100-300 remain on the Yamuna and Ganges rivers (Shaikh 2020), while on the east coast between 200 and 400 have been recorded at Satkosia on the River Mahanadi in Odisha (Debata et al. 2019, S. Debata in litt. 2020) and around 120 at Coringa Wildlife Sanctuary and Kakinada in Andhra Pradesh (eBird 2020, Wetlands International South Asia 2020). Individuals or very small numbers may occur almost anywhere around the coast (for example, recorded in 2018 at Kanyakumari, the southernmost tip of mainland India [S. Balachandran in litt. 2020]) and wander widely in central India during the non-breeding season (eBird 2020).
The population in Pakistan is now thought to be very small: 15 birds were found in surveys of Badin province in 2018 (Ali et al. 2018), close to and possibly connected with those wintering in Gujarat. One bird was observed in the Gulf of Mottama, Myanmar in 2018 (Chowdhury et al. 2020), but it does not seem likely that there is still a regular wintering population in Myanmar. The last regular known wintering group, near Sittwe, numbered 27 in 2008 fell to 9 in 2012, and none have been recorded since (C. Zöckler in litt. 2020).
On the basis of these numbers at wintering sites, the total population in 2020 is estimated at between 3,700 and 4,400 individuals, roughly equating to 2,450-2,900 mature individuals.
Present breeding records are from National Chambal Sanctuary, around 500 adults (Shaikh and Mendis 2019, Singh and Sharma 2018), River Mahanadi, 188-224 adults (Debata et al. 2019), Son Gharial Sanctuary, 50 adults (P. Shaikh in litt 2019), River Ganga, 450 adults (A. Kumar. in litt 2019) and Turtle Wildlife Sanctuary, 13 adults (five pairs) (Mital et al. 2019). Four pairs bred at Pong Dam in 2006, but no nesting has occurred there recently (Fernandes and Besten 2013, S. Balachandran in litt. 2020). The only other confirmed nesting in recent years has been in Bangladesh, where 45 individuals were observed at Chapai Nawabganj, Rajshahi division on 24 April 2016 and three nests subsequently located on 23 May 2016 (Kabir et al. 2016).
A small number may still breed in Pakistan, but there are no recent breeding records in the upper Indus plains and just two recent records of spring birds seem likely to have involved birds on passage, possibly to breeding sites in India (Z.A. Shaikh in litt. 2020).
As such the known breeding population is 1,204-1,280 mature individuals, lower than wintering numbers. This suggests there are additional breeding colonies to locate, and perhaps that a proportion of the mature population are not breeding in any particular year. When it is thought that the number of breeding individuals is reasonably well-known, such a discrepancy in breeding and wintering estimates can be a cause of concern, as it may indicate a severe restriction on breeding sites and hence a lower effective population size.
There are no confirmed records of breeding in Myanmar for over 80 years (C Zöckler in litt. 2020), but loss of the species from the country is likely to have occurred more recently. In south-east Asia the species has not been recorded many decades: in Lao PDR the last documented records are from 1929 (BirdLife 2001). In Cambodia the last record was made between 1950 and 1964, likely in 1960 or 1961 (Thomas and Poole 2003) when 6 birds were observed in Phnom Penh, at the confluence of the Tonle Sap, Mekong and Bassac Rivers (Thomas 1964, BirdLife International 2001). The last Viet Nam records are also from the 19th century (BirdLife International 2001).
Trend justification: The 2020 population estimate, 2,450-2,900 mature individuals, represents an estimated decline of 41% (33.9-45.9%) over three generations (16 years) from the 2001 population estimate of 4,000-6,000 mature individuals (Li et al. 2004, S. Balachandran in litt. 2005).
The species population was previously estimated as 10,000 individuals by Perennou et al.(1994), but it was thought likely to have fallen below this level given the evidence of declines throughout its range (BirdLife International 2001). On the basis of the 2001 Asian Waterbird Census count of 5,542 individuals (Li et al. 2004) and an estimate of the Indian population of 2,500 individuals (S. Balachandran in litt. 2005, noting that some individuals may have been included in both of these counts), a range of 6,000-10,000 individuals roughly equating to 4,000-6,700 mature individuals is taken as the best population estimate for the year 2001.
The rapid population reduction is supported by continuing range contractions. Formerly Indian Skimmer was common along the Indus, but had declined markedly during the twentieth century to the point where during the 1990s in Dera Ismail Khan district, only six records were made, of small groups pre- and post-breeding (Kylänpää 2000). In the past few years there have been only two records in northern Pakistan (Z.A. Shaikh in litt. 2020), a single bird and a pair, both of which moved on quickly. In the 1990s it was concluded that there were likely to still be a handful of breeding pairs in the northern Indus plains, the species is now no more than a rare transitory migrant with only historic breeding records (Z.A. Shaikh in litt. 2020). There continue to be occasional records in the breeding season along the Ayeyarwady River (C. Zockler in litt. 2020, Robson 2020), but it is now believed extinct as a breeding species in Myanmar (C Zöckler in litt. 2020). Similarly it has become a very rare visitor in Nepal, when two decades ago it had declined greatly but still occurred most years (BirdLife International 2001). Now, it is very rare with only a few recent records and is considered regionally Critically Endangered in Nepal (Inskipp et al. 2016). And Indian Skimmers are only very rare visitors to the north east Indian states with only 2-3 records in the past three decades (A. Choudhury in litt. 2020).
Asian Waterbird Census five-year counts in Bangladesh have declined steadily, with maximum counts of 5,400 in 2001–2005, 3,200 in 2005–2010, and 1,343 in 2011–2015 (Li et al. 2009, Mundkur et al. 2017, Chowdhury et al. 2020), but suffer from the likelihood of flocks being missed during a short survey period, as evidenced by the recent large count from Nijhum Dwip (D.K. Das in litt. 2020).
The declines appear to be driven by very low nesting success due to disturbance, predation (especially by feral dogs but also egg collecting by people) and hydrological changes due to dams and abstraction along breeding rivers (Debata et al. 2019, Shaikh et al. 2018, Shaikh and Mendis 2019, Shaikh 2020). As a result, the rate of population reduction appears steady, and is not predicted to either increase or decrease in the future unless there are significant interventions, negative or positive, on the breeding grounds.
Important Bird and Biodiversity Areas (IBA)
BirdLife International (2023) Species factsheet: Rynchops albicollis. Downloaded from
http://datazone.birdlife.org/species/factsheet/indian-skimmer-rynchops-albicollis on 08/12/2023.
Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from
http://datazone.birdlife.org on 08/12/2023.