Brown Rat (Rattus norvegicus) is in the Old World Mice and Rats family (Muridae). Across the U.S., iNaturalist users have logged 7,217 research-grade observations of it in our sample, peaking in September.
Seasonal pattern in the national data: year-round resident. Counts also reflect when people are out photographing, so compare months within a state rather than across states.
When to photograph Brown Rat: observations by month (U.S.)
About Brown Rat
The Brown rat (Rattus norvegicus), also referred to as the common rat, street rat, sewer rat, Hanover rat, Norway rat, Norwegian rat, or wharf rat is one of the best known and most common rats.From Wikipedia via iNaturalist — article, CC BY-SA.
Brown Rat by state
| State | Observations | Peak month | Main season |
|---|---|---|---|
| New York | 2,521 | September | Aug–Jul |
| California | 682 | April | Mar–Feb |
| Massachusetts | 677 | October | Sep–Aug |
| Washington | 478 | June | May–Apr |
| Illinois | 356 | December | Nov–Oct |
| Pennsylvania | 298 | September | Feb–Dec |
| District of Columbia | 254 | October | Feb–Dec |
| Maryland | 208 | July | Apr–Feb |
| Oregon | 176 | April | Jan–Nov |
| New Jersey | 134 | September | Aug–Apr |
| Utah | 121 | October | Sep–Aug |
| Virginia | 109 | April | Dec–Oct |
| Ohio | 104 | September | Mar–Jan |
| Texas | 104 | April | Feb–Apr |
| Connecticut | 88 | August | May–Mar |
| North Carolina | 80 | February | Jan–Dec |
| Michigan | 70 | April | Mar–Dec |
| Florida | 69 | March | Dec–May |
| Maine | 62 | April | Jan–Jun |
| Rhode Island | 60 | May | May–Oct |
| Vermont | 58 | April | Mar–Feb |
| Georgia | 53 | August | Jan–Nov |
| Tennessee | 48 | May | Mar–Jul |
| Wisconsin | 48 | July | Jun–Nov |
| New Hampshire | 39 | November | Nov–Feb |
| Colorado | 38 | February | Feb–Apr |
| Alaska | 33 | November | Nov–Dec |
| West Virginia | 32 | March | Mar–Mar |
| Minnesota | 28 | October | May–Dec |
| Delaware | 27 | January | Nov–Jan |
| Louisiana | 19 | May | May–Jul |
| Alabama | 18 | February | Feb–Apr |
| Missouri | 15 | May | May–May |
| Nevada | 12 | October | Sep–Dec |
| Oklahoma | 11 | September | Sep–Sep |
| Indiana | 10 | June | Jun–Jun |
| Kentucky | 10 | July | May–Aug |
| South Carolina | 9 | September | Sep–Sep |
| Arizona | 8 | April | Mar–Apr |
| Arkansas | 8 | June | Apr–Aug |
| Hawaii | 8 | January | Dec–Jan |
| Nebraska | 8 | August | Aug–Sep |
| Iowa | 6 | September | Sep–Sep |
| New Mexico | 5 | July | Apr–Jul |
Main season = months with at least 30% of the state's peak-month count.
Related mammals (Old World Mice and Rats)
Photography tips
- Keep a legal and safe distance: 100 yards from bears and wolves and 25 yards from other large animals in national parks.
- Dawn and dusk are peak activity times for most mammals.
- Use your car as a blind on wildlife drives.
FAQ
When is the best time to photograph Brown Rat?
Nationally, September has the most observations, with the main season from August to July.
Where is Brown Rat most often seen?
The most observations come from New York, California, Massachusetts.