The best word to describe the 2025 Common Nighthawk migration season (the third monitored in Franklin, NH) is unexpected. For the first time, the peak of migration—which has consistently occurred during the last week of August in Concord and Franklin—shifted to the first week of September. The change may have been weather-driven, but it was nonetheless remarkable given the species’ previous consistency in migration timing.  

The Franklin Falls count is conducted from the dam on the Pemigewasset River in the Army Corps of Engineers’ Franklin Falls Recreation Area. The site is a mile upstream from where the Pemigewasset meets the Winnipesaukee River to form the Merrimack River. For the background story on how I chose this strategic location, see the Fall 2022 and Fall 2023 issues of New Hampshire Bird Records, pages 21 and 12 respectively. 

The 2025 count began on the early date of August 13. My goal is to record a zero count at first so we are able to pinpoint the date of the beginning of migration. The goal of zero was reached 15 minutes later when showers and scattered thunderstorms hit. Another zero was recorded the next day. As if on cue, the first 39 birds of the season passed on August 15, a typical start date for the season. 

The next day featured the ideal weather nighthawk watchers look for, a modest southwest wind, bringing 143 nighthawks with it. Then, three out of the next four days suffered from unfavorable northwest winds, producing very low counts.   

Prior to August 23, I put out word that we expected a big flight for the 23rd. As a result, nine helpers turned out, the largest crowd ever for Franklin Falls. Some traveled across the state to witness the spectacle, and fortunately we recorded a total of 549 nighthawks, a good count, but not the blockbuster flight we expected. 

By August 25, the count only stood at 1,171 birds. My comment to my daily post to the NH Birds google group lamented that I was “beginning to have a funny feeling about this season.” Three days later, southwest winds returned, bringing 598 more nighthawks. A good count but not up to par for this date. The next three days brought more northwest winds, producing either a low or no count.   

By August 31, the end of the typical peak week for migration, I looked more closely at the weather conditions, since it “seemed” like there were a lot of days with northwest winds (not ideal conditions for nighthawk migration). Sure enough, after adding them up, the comparison looked like this: 

Table 1. Total number of days with northwest winds during Common Nighthawk migration counts at Franklin Falls, NH.

We now had a possible cause for the low counts for the season. At this point, I did not expect any more counts of any significance and predicted that there would only be a few days of single or double digit counts remaining and that this would probably be my last post to the NH Birds Google Group. 

I was wrong! A string of days with favorable winds returned for the next three out of four days resulting in two unprecedented quadruple-digit counts, including 1,239 on September 3, setting a state record high count for any date in September. More birds were counted in the last three days than in the prior two weeks. The nighthawks were back, but, encouraging as these numbers were, ultimately they would not make up for the deficit of August.   

Birds were still counted in good numbers on the late dates of September 9 and 10, later than I have ever counted. Ideally, we would count until we reach zero to determine the extent of the season, but the forecast of strong northwest winds over the next two days put an end to an unusual season. A total of 57.75 hours were invested over 25 days compared to 53.75 hours last year and 33.75 in 2023. The final season total was 6,111 Common Nighthawks (Table 2).

Table 2. Total Number of Common Nighthawks counted, with number of hours watched, during fall migration counts at Franklin Falls, NH.