Wilson's Warbler: arriving later
In recent years, Wilson's Warblers have tended to arrive later than average.
Swainson's Thrush: no change
So far, there has been no detectable change in Swainson's Thrush arrival dates over time.
Orange-crowned Warbler: arriving earlier
In recent years, Orange-crowned Warblers have tended to arrive earlier than average.
Fox Sparrow: no change
So far, there has been no detectable change in Fox Sparrow arrival dates over time.
Golden-crowned Sparrow: arriving earlier
In recent years, Golden-crowned Sparrows have tended to arrive earlier than average.
Hermit Thrush: arriving earlier
In recent years, Hermit Thrushes have tended to arrive earlier than average.
Ruby-crowned Kinglet: arriving earlier
In recent years, Ruby-crowned Kinglets have tended to arrive earlier than average.
The timing of bird arrivals in spring is thought to be adapted to the timing of food availability for successfully raising young, which may also be shifting with climate change. Earlier spring arrivals are consistent with warming trends and an earlier onset of spring. However, birds also need to be in good enough body condition to migrate, which might create delays in their arrivals at Palomarin.
Fall arrivals. Among species that arrive at Palomarin in the fall, Fox Sparrow hasn’t changed at all, while the others are arriving earlier. The timing of bird arrivals in fall likely reflect conditions to our north, with earlier fall arrivals suggesting an earlier end to their nesting season.
