Mussels and clamsIn Butler County, Ohio
Asian Clam
Corbicula fluminea (O. F. Müller, 1774)
Asian Clam in all of Ohio
Introduced and invasive status
Introduced in Ohio: iNaturalist (opens in a new tab)
Also listed
- Introduced and assessed as invasive in the lower 48 states
iNaturalist's volunteer curators list it as introduced in their Ohio checklist.
US-RIIS assesses a species as invasive when it causes, or is likely to cause, harm there, or is at least locally abundant and harmful ecologically, economically, or to health.
Status: Simpson A, Sellers E, Pagad S (2023). United States Register of Introduced and Invasive Species (US-RIIS), ver. 2.0. U.S. Geological Survey, https://doi.org/10.5066/P9KFFTOD (opens in a new tab)
Near Butler County
Range
Where it is recorded
Season shown in 0 of Ohio's 88 counties. Explore Ohio
- No result yet (22)
- Recorded, too few records for a result (60)
- Recorded, season not shown (6)
- Season shown (0)
Counties as a table
| County | Records |
|---|---|
| Adams County | Recorded, too few records for a result |
| Allen County | Recorded, too few records for a result |
| Ashland County | Recorded, too few records for a result |
| Ashtabula County | Recorded, too few records for a result |
| Athens County | Recorded, too few records for a result |
| Auglaize County | No qualifying records yet |
| Belmont County | Recorded, too few records for a result |
| Brown County | Recorded, too few records for a result |
| Butler County | 52 · Recorded, season not shown |
| Carroll County | Recorded, too few records for a result |
| Champaign County | Recorded, too few records for a result |
| Clark County | Recorded, too few records for a result |
| Clermont County | Recorded, too few records for a result |
| Clinton County | Recorded, too few records for a result |
| Columbiana County | Recorded, too few records for a result |
| Coshocton County | Recorded, too few records for a result |
| Crawford County | Recorded, too few records for a result |
| Cuyahoga County | 22 · Recorded, season not shown |
| Darke County | Recorded, too few records for a result |
| Defiance County | Recorded, too few records for a result |
| Delaware County | Recorded, too few records for a result |
| Erie County | Recorded, too few records for a result |
| Fairfield County | Recorded, too few records for a result |
| Fayette County | Recorded, too few records for a result |
| Franklin County | 70 · Recorded, season not shown |
| Fulton County | No qualifying records yet |
| Gallia County | Recorded, too few records for a result |
| Geauga County | Recorded, too few records for a result |
| Greene County | 26 · Recorded, season not shown |
| Guernsey County | No qualifying records yet |
| Hamilton County | 37 · Recorded, season not shown |
| Hancock County | Recorded, too few records for a result |
| Hardin County | No qualifying records yet |
| Harrison County | No qualifying records yet |
| Henry County | No qualifying records yet |
| Highland County | Recorded, too few records for a result |
| Hocking County | Recorded, too few records for a result |
| Holmes County | No qualifying records yet |
| Huron County | Recorded, too few records for a result |
| Jackson County | No qualifying records yet |
| Jefferson County | Recorded, too few records for a result |
| Knox County | Recorded, too few records for a result |
| Lake County | Recorded, too few records for a result |
| Lawrence County | No qualifying records yet |
| Licking County | No qualifying records yet |
| Logan County | Recorded, too few records for a result |
| Lorain County | Recorded, too few records for a result |
| Lucas County | Recorded, too few records for a result |
| Madison County | Recorded, too few records for a result |
| Mahoning County | Recorded, too few records for a result |
| Marion County | Recorded, too few records for a result |
| Medina County | Recorded, too few records for a result |
| Meigs County | No qualifying records yet |
| Mercer County | No qualifying records yet |
| Miami County | Recorded, too few records for a result |
| Monroe County | Recorded, too few records for a result |
| Montgomery County | Recorded, too few records for a result |
| Morgan County | Recorded, too few records for a result |
| Morrow County | Recorded, too few records for a result |
| Muskingum County | No qualifying records yet |
| Noble County | Recorded, too few records for a result |
| Ottawa County | Recorded, too few records for a result |
| Paulding County | No qualifying records yet |
| Perry County | No qualifying records yet |
| Pickaway County | Recorded, too few records for a result |
| Pike County | No qualifying records yet |
| Portage County | Recorded, too few records for a result |
| Preble County | Recorded, too few records for a result |
| Putnam County | No qualifying records yet |
| Richland County | Recorded, too few records for a result |
| Ross County | Recorded, too few records for a result |
| Sandusky County | No qualifying records yet |
| Scioto County | Recorded, too few records for a result |
| Seneca County | Recorded, too few records for a result |
| Shelby County | No qualifying records yet |
| Stark County | Recorded, too few records for a result |
| Summit County | 28 · Recorded, season not shown |
| Trumbull County | Recorded, too few records for a result |
| Tuscarawas County | Recorded, too few records for a result |
| Union County | Recorded, too few records for a result |
| Van Wert County | No qualifying records yet |
| Vinton County | Recorded, too few records for a result |
| Warren County | Recorded, too few records for a result |
| Washington County | No qualifying records yet |
| Wayne County | Recorded, too few records for a result |
| Williams County | No qualifying records yet |
| Wood County | Recorded, too few records for a result |
| Wyandot County | Recorded, too few records for a result |
No mapped range from the range source used, the USGS Gap Analysis Project, which maps land vertebrates only.
Season
When it is recorded
In Butler County
Early March to early May, middle week mid-April
Recorded in two separate seasons, each shown with its own early, middle and late weeks. A later season is not shown: most records are from one year.
Show over the bars
Records per week from 52 records in 6 of the 10 years from 2016 to 2025. Shows when people recorded it, not a season or how common it is.
Show as a table
| Week | Records of Asian Clam | Years recorded | Records of all species |
|---|---|---|---|
| Jan 4–10 | 0 | 0 | 59 |
| Jan 11–17 | 0 | 0 | 104 |
| Jan 18–24 | 0 | 0 | 111 |
| Jan 25–31 | 0 | 0 | 54 |
| Feb 1–7 | 0 | 0 | 62 |
| Feb 8–14 | 0 | 0 | 59 |
| Feb 15–21 | 0 | 0 | 70 |
| Feb 22–28 | 1 | 1 | 117 |
| Mar 1–7 | 2 | 2 | 221 |
| Mar 8–14 | 4 | 2 | 224 |
| Mar 15–21 | 1 | 1 | 250 |
| Mar 22–28 | 0 | 0 | 250 |
| Mar 29 – Apr 4 | 1 | 1 | 464 |
| Apr 5–11 | 2 | 1 | 681 |
| Apr 12–18 | 1 | 1 | 911 |
| Apr 19–25 | 8 | 2 | 1,134 |
| Apr 26 – May 2 | 2 | 2 | 1,163 |
| May 3–9 | 4 | 3 | 1,117 |
| May 10–16 | 0 | 0 | 724 |
| May 17–23 | 0 | 0 | 681 |
| May 24–30 | 0 | 0 | 518 |
| May 31 – Jun 6 | 0 | 0 | 531 |
| Jun 7–13 | 1 | 1 | 605 |
| Jun 14–20 | 2 | 2 | 566 |
| Jun 21–27 | 0 | 0 | 545 |
| Jun 28 – Jul 4 | 0 | 0 | 622 |
| Jul 5–11 | 0 | 0 | 580 |
| Jul 12–18 | 0 | 0 | 658 |
| Jul 19–25 | 0 | 0 | 618 |
| Jul 26 – Aug 1 | 1 | 1 | 664 |
| Aug 2–8 | 0 | 0 | 710 |
| Aug 9–15 | 0 | 0 | 555 |
| Aug 16–22 | 0 | 0 | 856 |
| Aug 23–29 | 1 | 1 | 1,185 |
| Aug 30 – Sep 5 | 0 | 0 | 2,105 |
| Sep 6–12 | 1 | 1 | 2,341 |
| Sep 13–19 | 0 | 0 | 1,284 |
| Sep 20–26 | 0 | 0 | 1,693 |
| Sep 27 – Oct 3 | 2 | 1 | 1,744 |
| Oct 4–10 | 6 | 2 | 1,330 |
| Oct 11–17 | 3 | 2 | 1,154 |
| Oct 18–24 | 7 | 1 | 745 |
| Oct 25–31 | 1 | 1 | 955 |
| Nov 1–7 | 0 | 0 | 261 |
| Nov 8–14 | 0 | 0 | 265 |
| Nov 15–21 | 0 | 0 | 197 |
| Nov 22–28 | 1 | 1 | 187 |
| Nov 29 – Dec 5 | 0 | 0 | 103 |
| Dec 6–12 | 0 | 0 | 173 |
| Dec 13–19 | 0 | 0 | 84 |
| Dec 20–26 | 0 | 0 | 89 |
| Dec 27 – Jan 2 | 0 | 0 | 106 |
In Ohio
Recorded all year
Recorded through most of the year, so there is no single season to show. Based on 617 records in 10 of the 10 years from 2016 to 2025, above the minimum of 20 records from 5 different years.
This week · Nov 8–14
Show over the bars
Records per week from 617 records in 10 of the 10 years from 2016 to 2025. Shows when people recorded it, not a season or how common it is.
Show as a table
| Week | Records of Asian Clam | Years recorded | Records of all species |
|---|---|---|---|
| Jan 4–10 | 2 | 2 | 6,211 |
| Jan 11–17 | 5 | 3 | 5,146 |
| Jan 18–24 | 2 | 1 | 4,645 |
| Jan 25–31 | 1 | 1 | 4,698 |
| Feb 1–7 | 5 | 3 | 6,023 |
| Feb 8–14 | 9 | 2 | 5,888 |
| Feb 15–21 | 8 | 1 | 5,436 |
| Feb 22–28 | 10 | 5 | 6,846 |
| Mar 1–7 | 9 | 5 | 8,321 |
| Mar 8–14 | 12 | 4 | 10,384 |
| Mar 15–21 | 12 | 6 | 12,620 |
| Mar 22–28 | 7 | 5 | 13,949 |
| Mar 29 – Apr 4 | 14 | 4 | 19,661 |
| Apr 5–11 | 15 | 6 | 26,860 |
| Apr 12–18 | 23 | 7 | 39,925 |
| Apr 19–25 | 19 | 5 | 41,623 |
| Apr 26 – May 2 | 19 | 6 | 56,391 |
| May 3–9 | 18 | 6 | 52,952 |
| May 10–16 | 8 | 3 | 53,785 |
| May 17–23 | 8 | 4 | 57,698 |
| May 24–30 | 8 | 4 | 54,651 |
| May 31 – Jun 6 | 14 | 7 | 53,099 |
| Jun 7–13 | 11 | 5 | 53,700 |
| Jun 14–20 | 17 | 6 | 56,625 |
| Jun 21–27 | 11 | 5 | 55,361 |
| Jun 28 – Jul 4 | 10 | 4 | 58,477 |
| Jul 5–11 | 12 | 6 | 61,336 |
| Jul 12–18 | 22 | 5 | 64,722 |
| Jul 19–25 | 16 | 8 | 69,753 |
| Jul 26 – Aug 1 | 22 | 7 | 59,416 |
| Aug 2–8 | 15 | 5 | 59,712 |
| Aug 9–15 | 13 | 7 | 55,994 |
| Aug 16–22 | 14 | 7 | 54,328 |
| Aug 23–29 | 11 | 7 | 51,772 |
| Aug 30 – Sep 5 | 15 | 7 | 57,167 |
| Sep 6–12 | 23 | 4 | 59,075 |
| Sep 13–19 | 18 | 6 | 54,543 |
| Sep 20–26 | 18 | 7 | 45,860 |
| Sep 27 – Oct 3 | 12 | 5 | 43,180 |
| Oct 4–10 | 22 | 5 | 37,841 |
| Oct 11–17 | 20 | 7 | 30,824 |
| Oct 18–24 | 21 | 6 | 21,156 |
| Oct 25–31 | 7 | 5 | 19,021 |
| Nov 1–7 | 8 | 5 | 14,172 |
| Nov 8–14 | 9 | 6 | 12,621 |
| Nov 15–21 | 5 | 3 | 7,965 |
| Nov 22–28 | 4 | 3 | 8,136 |
| Nov 29 – Dec 5 | 5 | 2 | 6,083 |
| Dec 6–12 | 6 | 4 | 6,004 |
| Dec 13–19 | 8 | 4 | 5,423 |
| Dec 20–26 | 4 | 3 | 5,661 |
| Dec 27 – Jan 2 | 10 | 5 | 8,459 |
What these results show
These results show when people recorded a species, not when or where it occurs. Missing weeks and low counts do not mean absence or scarcity, and counts are not abundance. Contributed records reflect where, when and what people chose to observe.
Identification
How to identify it
Look-alikes
Land cover
Often confused with
- Zebra Mussel Dreissena polymorpha22 identifications worldwide named one where the other was meant
From iNaturalist’s similar-species counts, refreshed monthly: confusions in Ohio first, then worldwide. Only species with an Ohio result are listed.
Land cover where it is recorded
| Land cover | Its recordsAll Ohio records |
|---|---|
| Developed | 40%49% |
| Forest | 31%31% |
| Open water | 14%3% |
| Wetland | 7%5% |
| Grassland and shrub | 4%0.9% |
| Barren | 2%0.6% |
| Farmland | 2%11% |
From 377 records placed within 100 m, beside all Ohio records placed the same way. People record where they go, so this shows where records come from, not where the species lives. Land cover: USGS Annual NLCD, 2025 (opens in a new tab)
Sources
Where these results come from
- Records from iNaturalist research-grade observations and expert-identified GBIF datasets, CC0, CC BY and CC BY-NC. Sources
- Seasons use the published method and its evidence thresholds. Methods
- See it on iNaturalist (opens in a new tab)OpenPhenology is independent and not affiliated with iNaturalist.
Records behind the Ohio result
617 records from 2 datasets.
- iNaturalist Research-grade Observations (opens in a new tab) · iNaturalist.org · 614 recordsiNaturalist contributors, iNaturalist (2026). iNaturalist Research-grade Observations. iNaturalist.org. Occurrence dataset https://doi.org/10.15468/ab3s5x accessed via GBIF.org on 2026-11-13.
- iNaturalist observations (opens in a new tab) · iNaturalist.org · 3 recordsiNaturalist. Available from https://www.inaturalist.org. Accessed 2026-11-13
To cite: the GBIF download doi:10.15468/dl.y2jkt8 (opens in a new tab).
A spreadsheet (CSV) with a link to each record, on iNaturalist or GBIF. Records whose location was hidden by the observer or the source are counted but not linked.