A disturbing, new trend exists along a stretch of the Delaware River at which a yearly census of ospreys’ nests, its adults and progeny is conducted by this birding enthusiast. Compared to the past many seasons, 2022 yielded significantly less offspring. Each nest surveyed is assumed to occupy a reproductive pair, as has been typical at least over the past decade; however, many nests have failed currently.
The three at the northeastern terminus of this avian study are located in the Landreth Channel, Keystone and Bristol ranges, as seen below:
Landreth, Keystone and Bristol nests were barren on June 30th. What appears to be an adult male sits atop Bristol’s channel buoy, while a pair is perched on the marker light at the northeastern tip of Burlington Island. For the prior five or six years, these locations had produced two or three chicks in each, except for Burlington Island’s light which doesn’t host a nest.
The next three are in the Devlin, Edgewater and Beverly Channels:
Two chicks and a parent were home at Devlin on the 3rd of July. The Edgewater nest was bustling with what looked to be three chicks and the nesting pair present. Beverly’s light hosted two chicks and a parent. Last year these pairs produced one, two and three chicks respectively.
Echo Beach’s pair were good for two or three chicks annually, as was the pair that roosted but no longer does on Pen Ryn’s light. This year Echo Beach’s nest was barren too, save for an adult on the tower. I’ve not a clue about the pair that roosts atop the abandoned conveyor in Delanco, N.J.
The conveyor’s ospreys are a recent addition to the study and last year had no chicks. The second photo above shows a vacant nest recently on June 4th.
One mile or two down the river comprises the Mud Island Range, atop which all three range markers sport ospreys’ nests. Note how closely they are to one another, unusual considering individual territorial disputes between raptors. I’m guessing the pairs are closely related.
The birds on the present-day Mud Island light and atop the range marker are also relatively new additions to the survey. They go back a few years. Prior to that, only the pair on the former light resided in the range. Last year, the working light’s pair had two chicks. This year I didn’t see any. One more trek up and down the river—probably in about three weeks—is in order to make the final determination of the population.
On the former light tower, the Andalusian pair had three young last season, which was common for them from year to year. Only two are evident as of the recent count. The range-marker ospreys hatched three last year, but only two for ’22.
For several years previously, this last group of ospreys was quite successful in spawning offspring. In 2021, the Pennypack Creek pair had one; the Riverton North and South birds had two chicks apiece. This season produced only one chick for the bunch, with that nestling being atop the Riverton North light in the Tacony Channel.
Assuming if all the nests seen occupying one or both adults earlier this season continue to host nesting pairs, 28 adults and 11 chicks inhabit the survey’s range. What’s disturbing to me about this is that last year’s adult tally was the same, but 27 chicks resulted, about 2½ times more than that of 2022. So what happened during this year to create such a shortage of offspring?
The flock arrived in mid-March, around the same time they do normally, give or take a few days to a week; so it’s not like they started too late to build-rebuild nests, find their mate, procreate and hatch progeny. Could it be because of climate change? Not sure about that. I tend to doubt if minimally rising water levels and temperatures have reached a point to discourage their reproductive success just yet.
What if they are suffering from some destructive contaminate like the outlawed DDT found in the food they eat (fish), or water they drink that caused their eggshells to weaken and crack, preventing a successful clutch of chicks? It could be a result of something imbibed from within their migratory routes and winter locations, possibly in South America. It would be tough to trace.
It seems unrealistic to consider a shortage of nesting pairs. Once mature, these birds return to mate typically in the region where they were born. A plethora of ospreys have been produced over the past eleven years here.
If next year’s census reports a drop in the numbers of chicks still throughout the area, a closer look into the reasons for the decline will be warranted.
I’ve been enjoying my new studio and homestead in Falls Township, but miss my old tromping grounds in Andalusia. Access to the ospreys and Delaware River was a lot closer, but it won’t discourage my future visits.
In closing, allow me to share my recent cover tunes recorded at Nine Gables:
I caution you about this next one being labeled NSFW, whose content is very un-politically correct for these times, having been written in the decadent, early 1980s when people didn’t get so offended. The cover was just fun to sing and play. Please be forewarned and take it “tongue-in-cheek.”
Thanks for stopping by and for your continued support.