Collection Summary
Agkistrodon piscivorus (Western Cottonmouth) has a total of 225 valid, non-duplicated collections representing 32 counties and 103 localities. There are a total of 70 collectors and 98 collection dates for the species. This results in a total of 107 expeditions for the species, a measure of unique date / collector(s) combinations. The earliest collection year for the species in Missouri is 1897 and its most recent collection year is 2023. The earliest and latest collection dates (independent of earliest and most recent collection years) are March 14 and November 28, respectively. If you have a new record to report, read the New Records section of the FAQ.
Collection Summary by County
| County | Localities | Collections | Collectors | Dates | Expeditions | Earliest Year | Latest Year | |
|---|---|---|---|---|---|---|---|---|
 | Barry | 4 | 4 | 2 | 3 | 3 | 2007 | 2020 |
| Bollinger | 4 | 12 | 7 | 6 | 7 | 1935 | 2012 |
| Butler | 4 | 10 | 4 | 4 | 5 | 1897 | 1909 |
| Camden | 3 | 3 | 3 | 3 | 3 | 1982 | 2023 |
| Cape Girardeau | 1 | 1 | 1 | 1 | 1 | ||
| Crawford | 1 | 1 | 1 | 1 | 1 | ||
| Dent | 1 | 17 | 2 | 2 | 2 | 1909 | 1909 |
| Dunklin | 3 | 4 | 3 | 3 | 3 | 1904 | 1959 |
| Henry | 1 | 1 | 1 | 1 | 1 | 2007 | 2007 |
| Hickory | 2 | 2 | 2 | 2 | 2 | 1983 | 2023 |
| Iron | 1 | 1 | 1 | 1 | 1 | 1973 | 1973 |
| Jefferson | 1 | 1 | 1 | 1 | 1 | ||
| Lawrence | 1 | 1 | 2 | 1 | 1 | 1991 | 1991 |
| Madison | 3 | 3 | 3 | 3 | 3 | 1973 | 2006 |
| Miller | 7 | 47 | 5 | 8 | 8 | 1939 | 1975 |
| Oregon | 1 | 1 | 1 | 1 | 1 | 1956 | 1956 |
| Ozark | 2 | 2 | 5 | 2 | 2 | 2007 | 2010 |
| Phelps | 1 | 1 | 1 | 1 | 1 | 2022 | 2022 |
| Pulaski | 3 | 3 | 5 | 2 | 3 | 1986 | 2022 |
| Ripley | 3 | 3 | 4 | 3 | 3 | 1939 | 2008 |
| Saint Clair | 3 | 5 | 3 | 3 | 3 | 1943 | 2009 |
| Sainte Genevieve | 1 | 1 | 1 | 1 | 1 | 2012 | 2012 |
| Saint Louis | 2 | 2 | 1 | 1 | 1 | 1995 | 1995 |
| Scott | 1 | 1 | 1 | 1 | 1 | 2001 | 2001 |
| Shannon | 5 | 7 | 6 | 6 | 6 | 1960 | 2020 |
| Stoddard | 20 | 63 | 19 | 29 | 32 | 1935 | 2016 |
| Stone | 5 | 5 | 7 | 5 | 5 | 2006 | 2020 |
| Taney | 2 | 2 | 2 | 2 | 2 | 1971 | 2014 |
| Texas | 2 | 2 | 7 | 2 | 2 | 1980 | 2003 |
| Washington | 1 | 1 | 1 | 1 | 1 | 1984 | 1984 |
| Wayne | 10 | 14 | 7 | 12 | 12 | 1935 | 2023 |
| Wright | 2 | 2 | 2 | 2 | 2 | 2004 | 2004 |