Editing Common blackbird (section)

==Status and conservation==
The common blackbird has an extensive range, estimated at {{convert|32.4|e6km2|e6sqmi|abbr=off}}, and a large population, including an estimated 79 to 160 million individuals in Europe alone. The species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (i.e., declining more than 30% in ten years or three generations), and is therefore evaluated as [[least concern]].<ref name=IUCN>{{cite iucn | author = BirdLife International | author-link = BirdLife International | title = ''Turdus merula'' | volume= 2014 | page = e.T22708775A62578644 | year = 2014 | doi=10.2305/IUCN.UK.2014-2.RLTS.T22708775A62578644.en}}</ref> In the western [[Palearctic]], populations are generally stable or increasing,<ref name=BWP>{{cite book | editor1-last = Snow | editor1-first = David |editor2-last= Perrins|editor2-first=Christopher M.| title = The Birds of the Western Palearctic concise edition (2 volumes) | publisher = Oxford University Press |year = 1998| location =Oxford | isbn = 0-19-854099-X }} p1215–1218</ref> but there have been local declines, especially on farmland, which may be due to agricultural policies that encouraged farmers to remove hedgerows (which provide nesting places), and to drain damp grassland and increase the use of [[pesticide]]s, both of which could have reduced the availability of invertebrate food.<ref name = RSPB>{{cite web|title= Threats|work=Blackbird |url= http://www.rspb.org.uk/wildlife/birdguide/name/b/blackbird/threats_dangers_and_survival.asp |publisher=Royal Society for the Protection of Birds |access-date=19 December 2007}}</ref>

The common blackbird was introduced to Australia by a bird dealer visiting [[Melbourne]] in early 1857,<ref name=OzPests/> and its range has expanded from its initial foothold in Melbourne and [[Adelaide]] to include all of southeastern Australia, including [[Tasmania]] and the [[Bass Strait]] islands.<ref name =backyard>{{cite web|title= Common Blackbird |work= Birds in Backyards |url= http://www.birdsinbackyards.net/finder/display.cfm?id=123|publisher= Australian Museum |access-date=30 December 2007}}</ref> The introduced population in Australia is considered a pest because it damages a variety of soft fruits in orchards, parks and gardens, including berries, cherries, stone fruit and grapes.<ref name="OzPests">Clarke, G. M.; Gross, S., Matthews, M.; Catling, P. C.; Baker, B.; Hewitt, C. L.; Crowther, D.; Saddler, S. R. (2000), ''Environmental Pest Species in Australia'', Australia: State of the Environment, Second Technical Paper Series (Biodiversity), Department of the Environment and Heritage, Canberra. {{HDL|102.100.100/203987}}</ref> It is thought to spread weeds, such as [[blackberry]], and may compete with native birds for food and nesting sites.<ref name=OzPests/><ref name=Oz>{{cite web |title= Blackbird |date=16 December 2014 |url=https://www.agric.wa.gov.au/birds/blackbird |publisher= Department of Agriculture, Western Australia |access-date=17 August 2017}}</ref>

The introduced common blackbird is, together with the native [[silvereye]] (''Zosterops lateralis''), the most widely distributed avian seed disperser in New Zealand. Introduced there along with the [[song thrush]] (''Turdus philomelos'') in 1862, it has spread throughout the country up to an elevation of {{convert|1500|m|ft|0}}, as well as outlying islands such as the [[Campbell Island group|Campbell]] and [[Kermadec Islands|Kermadecs]].<ref name = "Fallaetal79">Falla, R. A., R. B. Sibson, and E. G. Turbott (1979). ''The new guide to the birds of New Zealand and outlying islands''. Collins, Auckland. {{ISBN|0-00-216928-2}}</ref> It eats a wide range of native and exotic fruit, and makes a major contribution to the development of communities of naturalised woody weeds. These communities provide fruit more suited to non-endemic native birds and naturalised birds than to [[Endemism|endemic]] birds.<ref name= NZ>{{cite journal|last= Williams |first= Peter A |year= 2006|title= The role of blackbirds (''Turdus merula'') in weed invasion in New Zealand|journal= New Zealand Journal of Ecology |volume=30 |issue= 2|pages=285–291 |url=http://www.nzes.org.nz/nzje/free_issues/NZJEcol30_2_285.pdf}}</ref>

The numbers of blackbirds in Europe have been significantly reduced by the [[Usutu virus]] which is spread by mosquitoes.  This was detected in Italy in 1996 and has since spread to other countries including Germany and the UK.<ref>{{Cite web |title=Usutu virus decreases the population of common blackbirds in the outbreak region {{!}} German Center for Infection Research |url=https://www.dzif.de/en/usutu-virus-decreases-population-common-blackbirds-outbreak-region |access-date=2024-11-12 |website=www.dzif.de}}</ref><ref>{{Cite journal |last=Lawson |first=Becki |last2=Robinson |first2=Robert A. |last3=Briscoe |first3=Andrew G. |last4=Cunningham |first4=Andrew A. |last5=Fooks |first5=Anthony R. |last6=Heaver |first6=Joseph P. |last7=Hernández-Triana |first7=Luis M. |last8=John |first8=Shinto K. |last9=Johnson |first9=Nicholas |last10=Johnston |first10=Colin |last11=Lean |first11=Fabian Z. X. |last12=Macgregor |first12=Shaheed K. |last13=Masters |first13=Nicholas J. |last14=McCracken |first14=Fiona |last15=McElhinney |first15=Lorraine M. |date=2022-06-18 |title=Combining host and vector data informs emergence and potential impact of an Usutu virus outbreak in UK wild birds |url=https://www.nature.com/articles/s41598-022-13258-2 |journal=Scientific Reports |language=en |volume=12 |issue=1 |pages=10298 |doi=10.1038/s41598-022-13258-2 |issn=2045-2322|pmc=9206397 }}</ref>

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Turdus merula cabrerae  MHNT.ZOO.2010.11.186.14.jpg|''Turdus merula cabrerae '' - [[MHNT]]
Turdus merula merula  MHNT.ZOO.2010.11.186.11.jpg|''Turdus merula merula '' - [[MHNT]]
Turdus merula mauritanicus MHNT.ZOO.2010.11.186.23.jpg|''Turdus merula mauritanicus'' - [[MHNT]]
Turdus merula azorensis MHNT.ZOO.2010.11.189.8.jpg|''Turdus merula azorensis'' - [[MHNT]]
</gallery>