Editing Chinese mitten crab (section)

===Invasiveness===
This certain species of crab has been spreading rapidly from Asia (China and Korea) to North America and Europe, raising concerns that it competes with local species, and its burrowing nature damages embankments and clogs drainage systems.<ref>{{cite news |url=http://news.bbc.co.uk/2/hi/uk_news/england/4690988.stm |title=Exotic crabs in waterway invasion |work=[[BBC News]] |date=February 8, 2006}}</ref><ref>{{cite news |url=https://www.washingtonpost.com/wp-dyn/content/article/2006/08/07/AR2006080701309.html |title=Discovery of second invasive mitten crab raises worries |newspaper=[[The Washington Post]] |date=August 8, 2006 |author1=Elizabeth Williamson |author2=David A. Fahrenthold }}</ref> The crabs can make significant inland migrations. It was reported in 1995 that residents of [[Greenwich]] saw Chinese mitten crabs coming out of the [[River Thames]], and in 2014 one was found in the [[River Clyde|Clyde]], in Scotland.<ref>[https://www.bbc.com/news/uk-scotland-29365132 Invasion warning on Scotland's rivers], BBC News, 25 September 2014</ref> The crabs have also been known to take up residence in [[swimming pool]]s. In some places, the crabs have been found hundreds of miles from the sea. There is concern in areas with a substantial native crab fishery, such as the [[Chesapeake Bay]] in [[Maryland]] and the [[Hudson River]] in [[New York (state)|New York]] (both locations where the crabs were first spotted in 2005), as the impact of the invasion by this species on the native population is unknown.<ref>{{cite news |url=http://www.recordonline.com/apps/pbcs.dll/article?AID=/20070616/NEWS/706160336 |title=Fishermen Fear a Mitten Crab Invasion |author=Greg Bruno |date=June 16, 2006 |publisher=[[Times Herald-Record]] |access-date=June 27, 2007 |archive-date=February 13, 2020 |archive-url=https://web.archive.org/web/20200213182206/https://www.recordonline.com/apps/pbcs.dll/article?AID=/20070616/NEWS/706160336 |url-status=dead }}</ref>

It is generally illegal to import, transport, or possess live Chinese mitten crabs in the United States,<ref name="50CFR16.13">{{cite web |url=http://edocket.access.gpo.gov/cfr_2008/octqtr/50cfr16.13.htm |title=Title 50 – Wildlife and Fisheries. Part 16: Injurious Wildlife |work=[[Code of Federal Regulations]] |date=October 1, 2008}}</ref> as accidental release or escape risks spreading these crabs to uninfested waters. In addition, some states may have their own restrictions on possession of mitten crabs.<ref name="14CCR671">[[California Code of Regulations]], Title 14, Section 671</ref> California allows fishing for mitten crabs with some restrictions.<ref name="Bay Delta Region">{{cite web |url=http://www.delta.dfg.ca.gov/mittencrab/life_hist.asp |title=Chinese Mitten Crab: Life and History |publisher=[[California Department of Fish and Game]] |date=August 5, 1998 |access-date=December 25, 2008 |archive-url=https://web.archive.org/web/20090117002542/http://www.delta.dfg.ca.gov/mittencrab/life_hist.asp |archive-date=January 17, 2009 |url-status=dead }}</ref>

The Chinese mitten crab has been introduced into the [[Great Lakes]] several times but has not yet been able to establish a permanent population.<ref>{{cite web |author=P. D. N. Hebert |title=Canada's Freshwater Invertebrates: Decapoda |work=Canada's Aquatic Environments |publisher=[[University of Guelph]] |url=http://www.aquatic.uoguelph.ca/inverts/diver/arthropods/crust/decap.htm }}{{Dead link|date=July 2020 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

The [[Smithsonian]] is tracking the spread of the Chinese mitten crab and seeking help to determine the current distribution status of the mitten crab along all coasts of North America, especially [[Chesapeake Bay]], [[Delaware Bay]], [[Hudson River]], and [[San Francisco Bay]]. People are encouraged to report any mitten crab sightings, along with details (date, specific location, size) and a close-up photograph or specimen if possible. The first confirmed record along the [[East coast of the United States]] was in the Chesapeake Bay near [[Baltimore]], Maryland, in 2005.<ref name="SERC">{{cite web |url=http://mittencrab.nisbase.org/|title=Chinese Mitten Crabs have come to the East Coast of the United States: We are seeking reports of mitten crab sightings and collections |publisher=[[Smithsonian Environmental Research Center]] |date=May 8, 2011}}</ref><ref>
{{cite web
|author=<!-- not stated --> 
|date        = 
|title=Research Project: Invading Mitten Crabs - Tracking Their Current Status and Spread in North America
|url=https://serc.si.edu/research/projects/invading-mitten-crabs
|publisher=[[Smithsonian Environmental Research Center]]
|access-date=2005-04-30
}}
</ref>

Chinese mitten crabs have also invaded German waters, where they destroy fishing nets, hurt native fish species and damage local dams, causing damage of up to 80 million Euros. These crabs migrated from China to Europe as early as 1900 and were first documented by official German reports in 1912 from Aller River. After an investigation by German scientists in 1933, it was thought that the crabs migrated to Europe through ballast water in commercial ships. The crabs are the only freshwater crab species in Germany, and their tendency to dig holes has caused damage to industrial infrastructure and dams.<ref>3 September 2012, [http://news.sina.com.cn/c/2012-09-03/033825087121.shtml 中国大闸蟹入侵德国水域致德损失达8千万欧元] (Chinese mitten crabs invade German waters, cause damage of 80 million Euros), [[Sina.com|Sina News]]</ref>

The first time the crab was brought to Europe was most likely by commercial vessels. Ships must fill their ballast water tanks and during one of these filling events, it could have been the spawning time for the mitten crab. Since the larvae are free floating and {{convert|1.7|-|5|mm|frac=32|sp=us}} in size, it would have been easy for them to be swept into the ballast water tank. Once the ship reached Europe and emptied its tank, the crab larvae were released. Over time, this repetition would allow for a prominent mitten crab population in Europe.<ref name=":1" /> The crab has spread and can be found in Continental Europe, Southern France, United States of America (the San Francisco Bay), and the United Kingdom.  A 15-year period in Germany when the crabs were gradually entering Europe is known as the "establishment phase".<ref name=":0" />