Overview
Hello Ploverites!
We confirmed four additional snowy plover fledges for the season on Limantour Spit: two chicks from two different broods reached fledge age (i.e., 28 days after hatch) and are still being tended to by dad. We missed one fledge on North Beach this past week (i.e., we couldn't find the fledgling before it actually fledged and took off). We'll continue to search for this banded fledgling on our surveys—sometimes they'll stick around, looking for someone to hang out with until winter flocks form.
We began observing incubating adults disappearing from exclosed nests near North Beach parking lot, causing a few nest abandonments. There is a known risk of adult mortality with exclosures at other sites outside of Point Reyes, but we had not observed this here until this season. We could be losing adults to a nocturnal predator or to some other phenomenon, like HPAI (Highly Pathogenic Avian Influenza). Since losing our first adult, we began placing trap cameras to monitor exclosed nests in the area, but have yet to photograph anything besides common ravens visiting nests (ravens wouldn't be able to depredate the adults at nests). For now, we've decided to not use exclosures in the area, to prevent any further potential adult losses, in case the cause of adult loss is actually due to a predator. The mystery continues but we will continue to monitor this area more frequently.
If you have any questions, please feel free to contact Matt Lau via email.
CURRENT STATS:
- 34 total nests this season
- 8 active nest
- 15 hatched
- 11 failed nests
- 15–18 chicks on PRNS beaches
- 5 chicks fledged!
Heavy winds caused a Limantour nest to shift over to the edge of a mini-exclosure, making it vulnerable to predation by common ravens or other predators. Fortunately biologists found it first and fixed it!.
Photo credit: NPS/Matt Lau
Three nearly-week-old snowy plover chicks hiding amongst pickleweed on Limantour Spit mudflats. June 2023.
Photo credit: NPS/Matt Lau
Three snowy plover chicks from a recent Limantour Spit hatch. June 2023.
Photo credit: NPS/Matt Lau
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