Editing Common pochard (section)

== Conservation and threats ==
[[File:Common_Pochard_(Aythya_ferina)_(43770533960).jpg|thumb|Common pochards are strong fliers, capable of reaching speeds of {{convert|22|–|24|m/s|mph|abbr=on}}.{{sfn|Henningsson|Johansson|Hedenström|2010|p=94}}]]
The common pochard is one of the species protected by the ''[[Agreement on the Conservation of African-Eurasian Migratory Waterbirds]]'' (AEWA).{{sfn|AEWA|2018|p=21}} The [[International Union for Conservation of Nature]] rates the species as [[vulnerable species|vulnerable]]. Though it has a huge range and an extremely large population, there is evidence of precipitous declines in several regions. These reach somewhere in the range of 30–49 per cent over a 23-year period in Europe, for example.{{sfn|BirdLife International|2019}} In number of countries, its population is decreasing mainly due to the urbanization and transformation of the natural habitats, as well as due to overhunting.<ref>{{usurped|1=[https://web.archive.org/web/20170604070305/http://www.abcc-am.org/common-pochard.html Common Pochard (''Aythya ferina'') in Armenia.]}} 2017. In online publication: "The State of Breeding Birds of Armenia". TSE NGO, Armenian Bird Census Council. Retrieved on 10 October 2017.</ref> Introduced predators, such as the [[American mink]], have wreaked havoc on some populations. In Poland, for example, one studied population showed a 92 per cent decrease in the 30 years after mink first became established in the area.{{sfn|Brzeziński|Żmihorski|Nieoczym|Wilniewczyc|2020|p=144}} Birds, including [[carrion crow]]s and [[marsh harrier]]s are important nest predators.{{sfn|Albrecht|Hořák|Kreisinger|Weidinger|2006|p=789}}

A further threat to conservation efforts of this bird is that 75 official languages are spoken across the countries in which it is found, thus scientific knowledge is scattered across those different languages, and collaboration on conservation efforts is more difficult.<ref>{{Cite journal |first1=Pablo Jose|last1= Negret |first2=Scott C.|last2= Atkinson |first3=Bradley K.|last3= Woodworth |first4=Marina |last4=Corella Tor |first5=James R.|last5= Allan |first6=Richard A.|last6= Fuller |first7=Tatsuya |last7=Amano |doi=10.1371/JOURNAL.PONE.0267151 |id=Wikidata Q112271116 |issn=1932-6203 |issue=4 |journal=PLOS ONE |language=en |page=e0267151 |pmc=9020734 |pmid=35442973 |publication-date=20 April 2022 |title=Language barriers in global bird conservation |volume=17|doi-access=free|bibcode= 2022PLoSO..1767151N }}</ref>

It is the host for a variety of internal parasites, including [[Cestode|cestodes]], [[Nematode|nematodes]] and [[Trematode|trematodes]]. These include ''[[Paramonostomum aythyae]]'', a trematode which was first isolated from the common pochard; it is carried in the gut.{{sfn|Thebo|Naz|Dharejo|Siyal|2019|p=151–152}} In some locations, the common pochard may be an important vector of avian [[schistosome]]s, which are harboured in the bird's nasal and [[mesentery|mesenteric]] blood vessels. These schistosomes can be transmitted to humans who work or swim in the same wetland areas as the ducks, potentially causing [[cercarial dermatitis]].{{sfn|Athari|Gohar-Dehi|Rostami-Jalilian|2006|p=13–14}} Known blood parasites include ''[[Haemoproteus greineri]]'',  ''[[Haemoproteus nettionis]]'' and ''[[Plasmodium circumflexum]]''.{{sfn|Elahi|Islam|Hossain|Mohiuddin|2014}} It is also known to carry ''[[Toxoplasma gondii]]''.{{sfn|Mancianti|Nardoni|Mugnaini|Poli|2013|p=561}}