BirdsIn Summit County, Ohio
Double-crested Cormorant
Nannopterum auritum (R. P. Lesson, 1831)
Double-crested Cormorant in all of Ohio- Kingdom
- Animalia
- Phylum
- Chordata
- Class
- Aves
- Order
- Suliformes
- Family
- Phalacrocoracidae
- Genus
- Nannopterum
Near Summit County
Range
Where it is recorded
Season shown in 4 of Ohio's 88 counties. Its mapped range covers 88. Explore Ohio
- No result yet (0)
- Within its mapped range (21)
- Recorded, too few records for a result (48)
- Recorded, season not shown (15)
- Season shown (4)
Counties as a table
| County | Records | In mapped range |
|---|---|---|
| Adams County | Recorded, too few records for a result | Yes: migration |
| Allen County | No qualifying records yet | Yes: migration |
| Ashland County | Recorded, too few records for a result | Yes: migration |
| Ashtabula County | Recorded, too few records for a result | Yes: migration |
| Athens County | Recorded, too few records for a result | Yes: migration |
| Auglaize County | Recorded, too few records for a result | Yes: migration |
| Belmont County | No qualifying records yet | Yes: migration |
| Brown County | Recorded, too few records for a result | Yes: migration |
| Butler County | 31 · Recorded, season not shown | Yes: migration |
| Carroll County | Recorded, too few records for a result | Yes: migration |
| Champaign County | Recorded, too few records for a result | Yes: migration |
| Clark County | Recorded, too few records for a result | Yes: migration |
| Clermont County | 22 · Recorded, season not shown | Yes: migration |
| Clinton County | Recorded, too few records for a result | Yes: migration |
| Columbiana County | Recorded, too few records for a result | Yes: migration |
| Coshocton County | Recorded, too few records for a result | Yes: migration |
| Crawford County | No qualifying records yet | Yes: migration |
| Cuyahoga County | 238 · Recorded, season not shown | Yes: migration |
| Darke County | Recorded, too few records for a result | Yes: migration |
| Defiance County | Recorded, too few records for a result | Yes: migration |
| Delaware County | 21 · Recorded, season not shown | Yes: migration |
| Erie County | 66 · Recorded, season not shown | Yes: summer, migration |
| Fairfield County | Recorded, too few records for a result | Yes: migration |
| Fayette County | Recorded, too few records for a result | Yes: migration |
| Franklin County | 156 · Recorded, season not shown | Yes: migration |
| Fulton County | No qualifying records yet | Yes: migration |
| Gallia County | Recorded, too few records for a result | Yes: migration |
| Geauga County | Recorded, too few records for a result | Yes: migration |
| Greene County | 22 · Recorded, season not shown | Yes: migration |
| Guernsey County | Recorded, too few records for a result | Yes: migration |
| Hamilton County | 32 · Recorded, season not shown | Yes: migration |
| Hancock County | Recorded, too few records for a result | Yes: migration |
| Hardin County | Recorded, too few records for a result | Yes: migration |
| Harrison County | Recorded, too few records for a result | Yes: migration |
| Henry County | No qualifying records yet | Yes: migration |
| Highland County | Recorded, too few records for a result | Yes: migration |
| Hocking County | Recorded, too few records for a result | Yes: migration |
| Holmes County | No qualifying records yet | Yes: migration |
| Huron County | No qualifying records yet | Yes: migration |
| Jackson County | No qualifying records yet | Yes: migration |
| Jefferson County | No qualifying records yet | Yes: migration |
| Knox County | Recorded, too few records for a result | Yes: migration |
| Lake County | 55 · Season shown | Yes: migration |
| Lawrence County | No qualifying records yet | Yes: migration |
| Licking County | Recorded, too few records for a result | Yes: migration |
| Logan County | Recorded, too few records for a result | Yes: migration |
| Lorain County | 57 · Recorded, season not shown | Yes: migration |
| Lucas County | 68 · Recorded, season not shown | Yes: summer, migration |
| Madison County | Recorded, too few records for a result | Yes: migration |
| Mahoning County | Recorded, too few records for a result | Yes: migration |
| Marion County | Recorded, too few records for a result | Yes: migration |
| Medina County | 26 · Recorded, season not shown | Yes: migration |
| Meigs County | No qualifying records yet | Yes: migration |
| Mercer County | Recorded, too few records for a result | Yes: migration |
| Miami County | No qualifying records yet | Yes: migration |
| Monroe County | No qualifying records yet | Yes: migration |
| Montgomery County | 25 · Recorded, season not shown | Yes: migration |
| Morgan County | Recorded, too few records for a result | Yes: migration |
| Morrow County | Recorded, too few records for a result | Yes: migration |
| Muskingum County | Recorded, too few records for a result | Yes: migration |
| Noble County | No qualifying records yet | Yes: migration |
| Ottawa County | 67 · Recorded, season not shown | Yes: summer, migration |
| Paulding County | No qualifying records yet | Yes: migration |
| Perry County | Recorded, too few records for a result | Yes: migration |
| Pickaway County | Recorded, too few records for a result | Yes: migration |
| Pike County | No qualifying records yet | Yes: migration |
| Portage County | 35 · Season shown | Yes: migration |
| Preble County | Recorded, too few records for a result | Yes: migration |
| Putnam County | No qualifying records yet | Yes: migration |
| Richland County | Recorded, too few records for a result | Yes: migration |
| Ross County | No qualifying records yet | Yes: migration |
| Sandusky County | Recorded, too few records for a result | Yes: migration |
| Scioto County | No qualifying records yet | Yes: migration |
| Seneca County | Recorded, too few records for a result | Yes: migration |
| Shelby County | No qualifying records yet | Yes: migration |
| Stark County | 52 · Season shown | Yes: migration |
| Summit County | 204 · Season shown | Yes: migration |
| Trumbull County | Recorded, too few records for a result | Yes: migration |
| Tuscarawas County | Recorded, too few records for a result | Yes: migration |
| Union County | No qualifying records yet | Yes: migration |
| Van Wert County | Recorded, too few records for a result | Yes: migration |
| Vinton County | Recorded, too few records for a result | Yes: migration |
| Warren County | 34 · Recorded, season not shown | Yes: migration |
| Washington County | Recorded, too few records for a result | Yes: migration |
| Wayne County | 20 · Recorded, season not shown | Yes: migration |
| Williams County | Recorded, too few records for a result | Yes: migration |
| Wood County | Recorded, too few records for a result | Yes: summer, migration |
| Wyandot County | Recorded, too few records for a result | Yes: migration |
Season
When it is recorded
In Summit County
Early April to early November, middle week Aug 9–15
Middle week · Aug 9–15
This week · Nov 8–14
Show over the bars
Records per week from 204 records in 10 of the 10 years from 2016 to 2025. Shows when people recorded it, not how common it is. The grey bars show how many records of all species were made here each week, so you can see when recording itself was high or low; the season is not adjusted by them.
Recorded on 159 dates. Latest record: November 2025.
Show as a table
| Week | Records of Double-crested Cormorant | Years recorded | Records of all species |
|---|---|---|---|
| Jan 4–10 | 0 | 0 | 711 |
| Jan 11–17 | 0 | 0 | 665 |
| Jan 18–24 | 0 | 0 | 601 |
| Jan 25–31 | 0 | 0 | 526 |
| Feb 1–7 | 0 | 0 | 608 |
| Feb 8–14 | 0 | 0 | 619 |
| Feb 15–21 | 0 | 0 | 629 |
| Feb 22–28 | 0 | 0 | 748 |
| Mar 1–7 | 0 | 0 | 728 |
| Mar 8–14 | 2 | 1 | 852 |
| Mar 15–21 | 2 | 1 | 1,055 |
| Mar 22–28 | 3 | 2 | 1,007 |
| Mar 29 – Apr 4 | 3 | 3 | 1,005 |
| Apr 5–11 | 3 | 2 | 1,654 |
| Apr 12–18 | 14 | 6 | 2,454 |
| Apr 19–25 | 5 | 3 | 2,699 |
| Apr 26 – May 2 | 6 | 4 | 3,970 |
| May 3–9 | 1 | 1 | 3,569 |
| May 10–16 | 14 | 8 | 4,053 |
| May 17–23 | 3 | 3 | 3,509 |
| May 24–30 | 3 | 1 | 4,045 |
| May 31 – Jun 6 | 3 | 3 | 2,874 |
| Jun 7–13 | 4 | 4 | 3,158 |
| Jun 14–20 | 6 | 3 | 3,796 |
| Jun 21–27 | 8 | 5 | 3,501 |
| Jun 28 – Jul 4 | 1 | 1 | 3,968 |
| Jul 5–11 | 4 | 2 | 3,632 |
| Jul 12–18 | 0 | 0 | 4,051 |
| Jul 19–25 | 4 | 4 | 3,855 |
| Jul 26 – Aug 1 | 4 | 2 | 2,908 |
| Aug 2–8 | 5 | 5 | 3,828 |
| Aug 9–15 | 11 | 5 | 3,583 |
| Aug 16–22 | 16 | 7 | 3,535 |
| Aug 23–29 | 6 | 2 | 2,939 |
| Aug 30 – Sep 5 | 9 | 4 | 2,840 |
| Sep 6–12 | 6 | 3 | 2,758 |
| Sep 13–19 | 4 | 3 | 2,761 |
| Sep 20–26 | 6 | 4 | 2,646 |
| Sep 27 – Oct 3 | 10 | 6 | 2,089 |
| Oct 4–10 | 1 | 1 | 2,317 |
| Oct 11–17 | 5 | 4 | 1,944 |
| Oct 18–24 | 6 | 4 | 1,314 |
| Oct 25–31 | 14 | 7 | 1,272 |
| Nov 1–7 | 2 | 2 | 786 |
| Nov 8–14 | 1 | 1 | 761 |
| Nov 15–21 | 6 | 1 | 654 |
| Nov 22–28 | 1 | 1 | 703 |
| Nov 29 – Dec 5 | 0 | 0 | 503 |
| Dec 6–12 | 1 | 1 | 447 |
| Dec 13–19 | 1 | 1 | 496 |
| Dec 20–26 | 0 | 0 | 522 |
| Dec 27 – Jan 2 | 0 | 0 | 728 |
In Ohio
Late March to late June, middle week early May, and again mid-July to late November, middle week mid-September
Recorded in two separate seasons, each shown with its own early, middle and late weeks.
This week · Nov 8–14
Show over the bars
Records per week from 2,135 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 Double-crested Cormorant | Years recorded | Records of all species |
|---|---|---|---|
| Jan 4–10 | 7 | 4 | 6,211 |
| Jan 11–17 | 5 | 4 | 5,146 |
| Jan 18–24 | 3 | 1 | 4,645 |
| Jan 25–31 | 11 | 2 | 4,698 |
| Feb 1–7 | 4 | 3 | 6,023 |
| Feb 8–14 | 3 | 1 | 5,888 |
| Feb 15–21 | 1 | 1 | 5,436 |
| Feb 22–28 | 3 | 3 | 6,846 |
| Mar 1–7 | 1 | 1 | 8,321 |
| Mar 8–14 | 5 | 4 | 10,384 |
| Mar 15–21 | 21 | 6 | 12,620 |
| Mar 22–28 | 21 | 8 | 13,949 |
| Mar 29 – Apr 4 | 38 | 8 | 19,661 |
| Apr 5–11 | 48 | 9 | 26,860 |
| Apr 12–18 | 85 | 10 | 39,925 |
| Apr 19–25 | 65 | 10 | 41,623 |
| Apr 26 – May 2 | 74 | 10 | 56,391 |
| May 3–9 | 72 | 8 | 52,952 |
| May 10–16 | 91 | 10 | 53,785 |
| May 17–23 | 58 | 9 | 57,698 |
| May 24–30 | 40 | 9 | 54,651 |
| May 31 – Jun 6 | 33 | 10 | 53,099 |
| Jun 7–13 | 33 | 9 | 53,700 |
| Jun 14–20 | 29 | 9 | 56,625 |
| Jun 21–27 | 32 | 9 | 55,361 |
| Jun 28 – Jul 4 | 28 | 8 | 58,477 |
| Jul 5–11 | 32 | 9 | 61,336 |
| Jul 12–18 | 35 | 7 | 64,722 |
| Jul 19–25 | 48 | 9 | 69,753 |
| Jul 26 – Aug 1 | 30 | 9 | 59,416 |
| Aug 2–8 | 55 | 8 | 59,712 |
| Aug 9–15 | 50 | 9 | 55,994 |
| Aug 16–22 | 82 | 10 | 54,328 |
| Aug 23–29 | 82 | 9 | 51,772 |
| Aug 30 – Sep 5 | 95 | 9 | 57,167 |
| Sep 6–12 | 106 | 10 | 59,075 |
| Sep 13–19 | 111 | 10 | 54,543 |
| Sep 20–26 | 109 | 10 | 45,860 |
| Sep 27 – Oct 3 | 93 | 10 | 43,180 |
| Oct 4–10 | 77 | 10 | 37,841 |
| Oct 11–17 | 67 | 10 | 30,824 |
| Oct 18–24 | 51 | 9 | 21,156 |
| Oct 25–31 | 68 | 9 | 19,021 |
| Nov 1–7 | 32 | 8 | 14,172 |
| Nov 8–14 | 31 | 8 | 12,621 |
| Nov 15–21 | 19 | 7 | 7,965 |
| Nov 22–28 | 11 | 7 | 8,136 |
| Nov 29 – Dec 5 | 11 | 6 | 6,083 |
| Dec 6–12 | 8 | 4 | 6,004 |
| Dec 13–19 | 10 | 5 | 5,423 |
| Dec 20–26 | 4 | 4 | 5,661 |
| Dec 27 – Jan 2 | 7 | 4 | 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
- Neotropic Cormorant Nannopterum brasilianumOften confused in Ohio: 13 identifications in Ohio named one where the other was meant
- Great Blue Heron Ardea herodias87 identifications worldwide named one where the other was meant
- Common Loon Gavia immer80 identifications worldwide named one where the other was meant
- Canada Goose Branta canadensis51 identifications worldwide named one where the other was meant
- Green Heron Butorides virescens40 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 |
|---|---|
| Open water | 44%3% |
| Developed | 36%49% |
| Forest | 7%31% |
| Wetland | 7%5% |
| Grassland and shrub | 3%0.9% |
| Farmland | 2%11% |
| Barren | 2%0.6% |
From 773 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)
Finer identifications
Some Ohio records of this species were identified to a subspecies:
- Nannopterum auritum auritumNorthern Double-crested Cormorantsubspecies
Every one of these records counts toward the Double-crested Cormorant's season above.
Why some records go further than species
Many species vary from place to place. Groups of a species that look or sound a little different, and live in different areas, can be named as subspecies. Observers and experts only identify a record that far when it shows enough detail to tell them apart. Records without that detail count at the species level.
Names: Catalogue of Life.
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 Summit County result
204 records from 1 dataset.
- iNaturalist Research-grade Observations (opens in a new tab) · iNaturalist.org · 204 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.
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.