Editing Pelican (section)

==Status and conservation==

===Populations===
Globally, pelican populations are adversely affected by these main factors: declining supplies of fish through overfishing or water pollution, destruction of habitat, direct effects of human activity such as disturbance at nesting colonies, hunting and culling, entanglement in fishing lines and hooks, and the presence of pollutants such as [[DDT]] and [[endrin]]. Most species' populations are more or less stable, although three are classified by the [[IUCN]] as being at risk. All species breed readily in zoos, which is potentially useful for conservation management.<ref>{{Cite journal | last1 = Crivelli | first1= Alain J.| last2= Schreiber| first2= Ralph W.| doi = 10.1016/0006-3207(84)90063-6 | title = Status of the Pelecanidae | journal = Biological Conservation | volume = 30 | issue = 2 | pages = 147–56 | year = 1984| bibcode= 1984BCons..30..147C}}</ref>
[[File:(Pelecanus occidentalis) Tortuga Bay on the Island of Santa Cruz, Galápagos.JPG|thumb|''[[Pelecanus occidentalis]]'', [[Tortuga Bay]], Island of Santa Cruz, Galápagos]]
The combined population of brown and Peruvian pelicans is estimated at 650,000 birds, with around 250,000 in the United States and Caribbean, and 400,000 in Peru.{{efn|The US government has not accepted the elevation of the two taxa into separate species.<ref name=FWS/>}} The [[National Audubon Society]] estimates the global population of the brown pelican at 300,000.<ref>{{cite web|url=http://birds.audubon.org/species-search/Brown%20Pelican |title=Brown Pelican |access-date=9 August 2012 |work=Species profile |publisher=National Audubon Society |url-status=dead |archive-url=https://web.archive.org/web/20131105203741/http://birds.audubon.org/species-search/Brown%20Pelican |archive-date=5 November 2013 }}</ref> Numbers of brown pelican plummeted in the 1950s and 1960s, largely as a consequence of environmental DDT pollution, and the species was listed as endangered in the US in 1970. With restrictions on DDT use in the US from 1972, its population has recovered, and it was delisted in 2009.<ref name="FWS">{{cite journal|author=Fish and Wildlife Service, Department of the Interior|date=17 November 2009|title=Endangered and Threatened Wildlife and Plants; Removal of the Brown Pelican (''Pelecanus occidentalis'') From the Federal List of Endangered and Threatened Wildlife|journal=Federal Register|volume=74|issue=220|pages=59444–72|url=http://www.gpo.gov/fdsys/pkg/FR-2009-11-17/pdf/E9-27402.pdf#page=1}}</ref><ref name="SF">{{cite news| author = Cappiello, Dina| title= Brown pelicans off endangered species list| url= http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2009/11/12/BAP71AIOJD.DTL| newspaper= San Francisco Chronicle |date= 12 November 2009 | access-date=13 June 2012}}</ref>

The Peruvian pelican is listed as near threatened because, although the population is estimated by [[BirdLife International]] to exceed 500,000 mature individuals, and is possibly increasing, it has been much higher in the past. It declined dramatically during the 1998 [[El Niño–Southern Oscillation|El Niño]] event and could experience similar declines in the future. Conservation needs include regular monitoring throughout the range to determine population trends, particularly after El Niño years, restricting human access to important breeding colonies, and assessing interactions with fisheries.<ref>{{cite web |url=http://www.birdlife.org/datazone/speciesfactsheet.php?id=3816 |title=Peruvian Pelican |access-date=7 August 2012 |work=BirdLife species factsheet |publisher=BirdLife International}}</ref>

The spot-billed pelican has an estimated population between 13,000 and 18,000 and is considered to be near threatened in the IUCN Red List of Threatened Species. Numbers declined substantially during the 20th century, one crucial factor being the eradication of the important [[Sittaung River|Sittaung valley]] breeding colony in Burma through deforestation and the loss of feeding sites.<ref>{{cite web |url=http://www.birdlife.org/datazone/speciesfactsheet.php?id=3812 |title=Spot-billed Pelican |access-date=11 August 2012 |work=Species factsheet |publisher=BirdLife International}}</ref> The chief threats it faces are from habitat loss and human disturbance, but populations have mostly stabilised following increased protection in India and Cambodia.<ref name="iucnphillippenis">{{cite iucn |author=BirdLife International |date=2017 |title=''Pelecanus philippensis'' |volume=2017 |page=e.T22697604A117970266 |doi=10.2305/IUCN.UK.2017-3.RLTS.T22697604A117970266.en |access-date=11 November 2021}}</ref>

The pink-backed pelican has a large population ranging over much of [[sub-Saharan Africa]]. In the absence of substantial threats or evidence of declines across its range, its conservation status is assessed as being of least concern. Regional threats include the drainage of wetlands and increasing disturbance in southern Africa. The species is susceptible to [[bioaccumulation]] of toxins and the destruction of nesting trees by logging.<ref>{{cite web |url=http://www.birdlife.org/datazone/speciesfactsheet.php?id=3810|title=Pink-backed Pelican |access-date=7 August 2012 |work=BirdLife species factsheet |publisher=BirdLife International}}</ref>

The American white pelican has increased in numbers,<ref name=Keith05/> with its population estimated at over 157,000 birds in 2005, becoming more numerous east of the continental divide, while declining in the west.<ref>{{cite journal |last1=King |first1=D. Tommy |last2=Anderson |first2=Daniel W |title=Recent Population Status of the American White Pelican: A Continental Perspective |year=2005|journal= USDA National Wildlife Research Center – Staff Publications. |issue=Paper 40|pages=48–54 |url=http://digitalcommons.unl.edu/icwdm_usdanwrc/40}}</ref> However, whether its numbers have been affected by exposure to pesticides is unclear, as it has also lost habitat through wetland drainage and competition with recreational use of lakes and rivers.<ref name=Keith05/><!-- cites previous two sentences -->

[[File:Pelecanus onocrotalus -Kenya -several-8.jpg|right|thumb|[[Great white pelican]]s loafing in Kenya]]
Great white pelicans range over a large area of Africa and southern Asia. The overall trend in numbers is uncertain, with a mix of regional populations that are increasing, declining, stable, or unknown, but no evidence has been found of rapid overall decline, and the status of the species is assessed as being of least concern. Threats include the drainage of wetlands, persecution and sport hunting, disturbance at the breeding colonies, and contamination by pesticides and heavy metals.<ref>{{cite web |url= http://www.birdlife.org/datazone/speciesfactsheet.php?id=3809|title=Great White Pelican |access-date=7 August 2012 |work=BirdLife species factsheet |publisher=BirdLife International}}</ref>

The Dalmatian pelican has a population estimated at between 10,000 and 20,000 following massive declines in the 19th and 20th centuries. The main ongoing threats include hunting, especially in eastern Asia, disturbance, coastal development, collision with overhead power lines, and the over-exploitation of fish stocks.<ref>{{cite web |url=http://www.birdlife.org/datazone/speciesfactsheet.php?id=3811 |title= Dalmatian Pelican |access-date=9 August 2012 |work=Species factsheet |publisher=BirdLife International}}</ref> It is listed as near threatened by the IUCN Red List of Threatened Species as the population trend is downwards, especially in Mongolia, where it is nearly extinct. However, several European colonies are increasing in size and the largest colony for the species, at the [[Small Prespa Lake]] in Greece, has reached about 1,400 breeding pairs following conservation measures.<ref name="iucncrispus">{{Cite iucn | author = BirdLife International | title = ''Pelecanus crispus'' | volume = 2017 | page = e.T22697599A119401118 | date = 2017 | doi = 10.2305/IUCN.UK.2017-3.RLTS.T22697599A119401118.en }}</ref>

Widespread across Australia,<ref name=Keith05/> the Australian pelican has a population generally estimated at between 300,000 and 500,000 individuals.<ref>{{cite book|author1=Robin, Libby |author2=Joseph, Leo |author3=Heinsohn, Robert | title = Boom & Bust: Bird Stories for a Dry Country| url = https://books.google.com/books?id=W_9jMwwC4foC| year = 2009| publisher = CSIRO Publishing| location = Collingwood, Victoria| isbn = 978-0643096066| page = 97 }}</ref> Overall population numbers fluctuate widely and erratically depending on wetland conditions and breeding success across the continent. The species is assessed as being of least concern.<ref>{{cite web |url= http://www.birdlife.org/datazone/speciesfactsheet.php?id=3813|title= Australian Pelican |access-date=7 August 2012 |work=BirdLife species factsheet |publisher=BirdLife International}}</ref>

===Culling and disturbance===
Pelicans have been persecuted by humans for their perceived competition for fish, despite the fact that their diet overlaps little with fish caught by people.<ref name=Keith05/> Starting in the 1880s, American white pelicans were clubbed and shot, their eggs and young were deliberately destroyed, and their feeding and nesting sites were degraded by water management schemes and wetland drainage.<ref name=Keith05/> Even in the 21st century, an increase in the population of American white pelicans in southeastern Idaho in the US was seen to threaten the recreational [[cutthroat trout]] fishery there, leading to official attempts to reduce pelican numbers through systematic harassment and [[culling]].<ref>{{cite book |title=Management of American White Pelicans in Idaho. A Five-year Plan (2009–2013) to Balance American White Pelican and Native Cutthroat Trout Conservation Needs and Manage Impacts to Recreational Fisheries in Southeast Idaho |author=Wackenhut, M. |date=17 August 2009 |publisher=Idaho Fish & Game |url=http://fishandgame.idaho.gov/public/wildlife/planPelican.pdf |access-date=21 July 2012 |url-status=dead |archive-url=https://web.archive.org/web/20120824035950/http://fishandgame.idaho.gov/public/wildlife/planPelican.pdf |archive-date=24 August 2012 }}</ref>

Great white pelicans on Dyer Island, in the Western Cape region of South Africa, were culled during the 19th century because their predation of the eggs and chicks of [[guano]]-producing seabirds was seen to threaten the livelihood of the guano collectors.<ref name=esr/> More recently, such predation at South African seabird colonies has impacted on the conservation of threatened seabird populations, especially crowned cormorants, Cape cormorants, and [[bank cormorant]]s. This has led to suggestions that pelican numbers should be controlled at vulnerable colonies.<ref name=esr/>

Apart from [[habitat destruction]] and deliberate, targeted persecution, pelicans are vulnerable to disturbance at their breeding colonies by birdwatchers, photographers, and other curious visitors. Human presence alone can cause the birds to accidentally displace or destroy their eggs, leave hatchlings exposed to predators and adverse weather, or even abandon their colonies completely.<ref>{{cite web |url=http://ec.europa.eu/environment/life/project/Projects/index.cfm?fuseaction=home.showFile&rep=file&fil=CodeofPractice.pdf |title= Code of Practice for the Protection of the Dalmatian Pelican |access-date=3 August 2012 |work=Information leaflet |publisher=Life Natura Program}}</ref><ref>{{cite web |url=http://blogs.mprnews.org/statewide/2012/05/loving_em_to_death/ |title=Loving 'em to death |access-date=14 February 2017 |work=Statewide |first=Dan |last=Gunderson |publisher=MPR News |date=16 May 2012 }}</ref><ref name="cfgc07">{{cite book |title=Status Review of California Brown Pelican |author1=Burkett, Esther |author2=Logsdon, Randi J. |author3=Fien, Kristi M. |year=2007 |series=California Fish and Game Commission Reports |publisher=U.S. Environmental Protection Agency, Office of Planning and Evaluation |url=http://www.dfg.ca.gov/wildlife/nongame/publications/docs/BRPEStatusReviewJan0308.pdf |url-status=dead |archive-url=https://web.archive.org/web/20111220103002/http://www.dfg.ca.gov/wildlife/nongame/publications/docs/BRPEStatusReviewJan0308.pdf |archive-date=20 December 2011 }}</ref>

===Poisoning and pollution===
{{multiple image
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| image1 = Gulf-Oiled-Pelicans-June-3-2010.jpg
| alt1 = Group of pelicans in captivity covered with oil
| caption1 = [[Brown pelican]]s, covered with oil, after the [[Deepwater Horizon oil spill|''Deepwater Horizon'' oil spill]] of 2010

| image2 = Pelican wash from oil spill Louisiana 13 Dawn IBRRC 2010.05.04 B6X2141.jpg
| alt2 = People washing oiled brown pelican
| caption2 = Oiled brown pelican being washed at a rescue center in Fort Jackson, 2010
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DDT pollution in the environment was a major cause of decline of brown pelican populations in North America in the 1950s and 1960s. It entered the oceanic [[food web]], contaminating and accumulating in several species, including one of the pelican's primary food fish – the [[northern anchovy]]. Its [[metabolite]] [[Dichlorodiphenyldichloroethylene|DDE]] is a reproductive [[wikt:toxicant|toxicant]] in pelicans and many other birds, causing eggshell thinning and weakening, and consequent breeding failure through the eggs being accidentally crushed by brooding birds. Since an effective ban on the use of DDT was implemented in the US in 1972, the eggshells of breeding brown pelicans there have thickened and their populations have largely recovered.<ref name="usepa1980">{{cite book |title= National accomplishments in pollution control, 1970–1980: some case histories|isbn=1236274539 |author=Anon |year=1980 |publisher= U.S. Environmental Protection Agency, Office of Planning and Evaluation|pages=183–184}}</ref><ref>{{cite web |url= http://www.stanford.edu/group/stanfordbirds/text/essays/DDT_and_Birds.html |title=DDT and Birds |access-date=6 August 2012 |author1=Ehrlich, Paul R. |author2=Dobkin, David S. |author3=Wheye, Darryl |publisher=Stanford University |year=1988}}</ref>

In the late 1960s, following the major decline in brown pelican numbers in Louisiana from DDT poisoning, 500 pelicans were imported from Florida to augment and re-establish the population; over 300 subsequently died in April and May 1975 from poisoning by the pesticide endrin.<ref>{{cite web |url= https://news.google.com/newspapers?nid=861&dat=19820428&id=075dAAAAIBAJ&pg=3543,7071462|title= Bird species regroup with residue decline |access-date=8 August 2012 |work=The Victoria Advocate: Julius Ermis' Outdoors |author=Ermis, Julius |date=29 April 1982}}</ref> About 14,000 pelicans, including 7,500 American white pelicans, perished from [[botulism]] after eating fish from the [[Salton Sea]] in 1990.<ref name=Keith05/> In 1991, abnormal numbers of brown pelicans and [[Brandt's cormorant]]s died at [[Santa Cruz, California]], when their food fish (anchovies) were contaminated with [[neurotoxin|neurotoxic]] [[domoic acid]], produced by the [[diatom]] ''[[Pseudo-nitzschia]]''.<ref>{{cite journal |author1=Work, Thierry M. |author2=Barr, Bradd |author3=Beale, Allison M. |author4=Fritz, Lawrence |author5=Quilliam, Michael A. |author6=Wright, Jeffrey L.C. |year=1993|title=Epidemiology of domoic acid poisoning in Brown Pelicans (''Pelecanus occidentalis'') and Brandt's Cormorants (''Phalacrocorax penicillatus'') in California|jstor=20460314 |journal=Journal of Zoo and Wildlife Medicine |volume=24 |issue=1 |pages=54–62}}</ref>

As waterbirds that feed on fish, pelicans are highly susceptible to [[oil spill]]s, both directly by being oiled and by the impact on their food resources. A 2007 report to the California Fish and Game Commission estimated that during the previous 20 years, some 500–1,000 brown pelicans had been affected by oil spills in California.<ref name=cfgc07/> A 2011 report by the [[Center for Biological Diversity]], a year after the April 2010 [[Deepwater Horizon oil spill]], said that 932 brown pelicans had been collected after being affected by oiling and estimated that ten times that number had been harmed as a result of the spill.<ref>{{cite web |url=http://www.biologicaldiversity.org/programs/public_lands/energy/dirty_energy_development/oil_and_gas/gulf_oil_spill/pdfs/GulfWildlifeReport_2011.pdf |title=A Deadly Toll |access-date=6 August 2012 |work=Report |publisher=Center for Biological Diversity |date= April 2011}}</ref>

Where pelicans interact with fishers, through either sharing the same waters or scavenging for fishing refuse, they are especially vulnerable to being hooked and entangled in both active and discarded fishing lines. [[Fish hook]]s are swallowed or catch in the skin of the pouch or webbed feet, and strong [[monofilament fishing line]] can become wound around bill, wings, or legs, resulting in crippling, starvation, and often death. Local rescue organisations have been established in North America and Australia by volunteers to treat and rehabilitate injured pelicans and other wildlife.<ref>{{cite web |url=http://www.sbwcn.org/#!news-&-events/vstc3=pelican-crisis |title=The Brown Pelican Crisis|access-date=5 August 2012 |work=News and Events |publisher= Santa Barbara Wildlife Care Network }}</ref><ref>{{cite web |url=http://collier.ifas.ufl.edu/SeaGrant/pubs/PelicanPub.pdf |title=Quick Reference for Rescuing Hooked Pelicans |access-date=5 August 2012 |publisher=University of Florida}}</ref><ref>{{cite book |title= The Impact of Recreational Fishing on Estuarine Birdlife on the Far North Coast of New South Wales |author1=Ferris, Lance |author2=Ferris, Rochelle |year=2004 |publisher=Australian Seabird Rescue |location=Ballina, New South Wales |url= https://www.box.com/shared/8fcmrpsvobv8y7yg0uap }}</ref>

===Parasites and disease===
As with other [[bird families]], pelicans are susceptible to a variety of [[parasitism|parasites]]. [[Avian malaria]] is carried by the [[mosquito]] ''Culex pipens'', and high densities of these biting insects may force pelican colonies to be abandoned. [[Leech]]es may attach to the [[cloaca|vent]] or sometimes the inside of the pouch.<ref name="Rothschild ">{{cite book |title= Fleas, Flukes and Cuckoos. A Study of Bird Parasites |author= Rothschild, Miriam |author-link= Miriam Rothschild |author2= Clay, Theresa |year= 1953 |publisher= Collins |location= London |pages = 32, 121, 147, 215 |url= https://archive.org/details/fleasflukescucko017900mbp |access-date=29 June 2012}}</ref> A study of the parasites of the American white pelican found 75 different species, including [[cestoda|tapeworms]], [[trematoda|flukes]], [[fly|flies]], [[flea]]s, [[tick]]s, and [[nematode]]s.

The brown pelican has a similarly extensive range of parasites. The nematodes ''Contracaecum multipapillatum'' and ''C. mexicanum'' and the [[trematode]] ''Ribeiroia ondatrae'' have caused illness and mortality in the [[Puerto Rico|Puerto Rican]] population, possibly endangering the pelican on this island.<ref name="dyer">{{cite journal | last= Dyer | first= William G. | author2= Williams, Ernest H. Jr | author3= Mignucci-Giannoni, Antonio A. | author4= Jimenez-Marrero, Nilda M. | author5= Bunkley-Williams, Lucy | author6= Moore, Debra P. | author7= Pence Danny B. | year= 2002 | title= Helminth and Arthropod Parasites of the Brown Pelican, ''Pelecanus occidentalis'', in Puerto Rico, with a Compilation of all Metazoan Parasites Reported from this Host in the Western Hemisphere | journal= Avian Pathology | volume= 31 | issue= 5 | pages= 441–48 | doi= 10.1080/0307945021000005815 | pmid= 12427338 | s2cid= 21351183 | df= dmy-all | doi-access= free }}</ref>

Many pelican parasites are found in other bird groups, but several [[louse|lice]] are very [[host (biology)|host-specific]].<ref name= overstreet/> Healthy pelicans can usually cope with their lice, but sick birds may carry hundreds of individuals, which hastens a sick bird's demise. The pouch louse ''Piagetiella peralis'' occurs in the pouch and so it cannot be removed by [[preening]]. While this is usually not a serious problem even when present in such numbers that it covers the whole interior of the pouch, sometimes inflammation and bleeding may occur from it and harm the host.<ref name="overstreet">{{cite journal | last= Overstreet | first= Robin M. |author2=Curran, Stephen S. | year=2005 | title= Parasites of the American White Pelican | journal= Gulf and Caribbean Research | volume= 17 |pages= 31–48 | url =http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1430&context=parasitologyfacpubs&sei-redir=1 |format =PDF| doi= 10.18785/gcr.1701.04 | doi-access= free | bibcode= 2005GCRes..17....4O }}</ref>

In May 2012, hundreds of Peruvian pelicans were reported to have perished in [[Peru]] from a combination of starvation and [[roundworm]] infestation.<ref name="peru">{{cite web|title= Pelícanos en La Libertad murieron por desnutrición y parasitosis | date= 4 May 2012 | url= http://peru.com/2012/05/04/actualidad/nacionales/pelicanos-libertad-murieron-desnutricion-y-parasitosis-noticia-62307 | language = es | publisher=Peru.com, 4 May 2012 | access-date=29 June 2012}}</ref>