Friday, September 26, 2025

The Fujiwhara Effect

CAPTAIN SAMS 
We banded 15 new birds and had 7 recaptures of 12 species. We followed up yesterday's first-of-the-season Tufted Titmouse with 3 more today. As Michael mentioned yesterday, the main part of Kiawah is LOADED with titmice but we rarely captured them out on spit. These are mainly young birds dispersing from their natal territories and probably won't stick around for very long. 

South winds continue to keep banding slow however there is a cold front that working its way across South Carolina and should reach the coast by tomorrow morning. We may see some rain with this front which may or may not affect our ability to open nets in the morning. Either way, Sunday looks promising with north winds and hopefully some birds will be moving behind the front.

With that said, we are also monitoring a couple of tropical systems in the Atlantic Ocean. Hurricane Humberto (Category 3) is currently 1,500 miles away from us. One its own, this storm is not projected to have much impact on us as the predicted track has it staying well offshore. 

However...DUN, Dun, dun. 

Another system, currently called Invest 94L, is brewing in the Caribbean near the Dominican Republic and Haiti, and is expected to be elevated to a tropical storm (Imelda). Future storm Imelda is expected to have some impacts to the Southeast US (in particular to South Carolina) as its predicted track is closer to the US. Because of the proximity of these two storms to each other, the current predictions could all change as the Fujiwhara Effect could be triggered. The Fujiwhara Effect is a phenomenon where two major storms interact with each other even if the storms are several hundred miles apart. If one storm is stronger than the other, the smaller one will orbit around it and eventually be absorbed into it. If two storms are closer in strength, they may gravitate towards each other until they reach a common point and merge, or just spin each other around until shooting off into their own paths. 

So, what can expect from this? There are three main scenarios based on computer models.

1. Invest 94L develops into a slow moving tropical storm or hurricane that eventually moves out to sea.

2. Invest 94L develops into a tropical storm or hurricane and makes landfall around Georgia and South Carolina bring with is flooding rain and high winds.

3. The high pressure that is built up behind the cold front could block the storm from reaching the east coast and instead it just stays out to sea. 

We will be monitoring the situation over the next couple of days hoping for scenario #1 or #3, and that Humberto is strong enough to pull Imelda out into the Atlantic for a mid-ocean rendezvous.  

-Aaron
   

LITTLE BEAR
It was another slow day while these storm systems bring us heat and seem to prevent birds from arriving. We banded 12 birds and had 4 recaptures, from 6 species. Tomorrow is looking a bit rainy, but hopefully it will pass quickly and bring some birds! 

- Camille 
Painted Bunting (hatch year, unknown sex)


  SpeciesCaptain Sam'sLittle Bear
NewRecapsNewRecaps
Downy Woodpecker
-1--
White-eyed Vireo
1---
Red-eyed Vireo
---1
Tufted Titmouse
3---
Blue-gray Gnatcatcher
1---
House Wren
1---
Brown Thrasher
1---
Northern Mockingbird
1---
Common Yellowthroat
2381
American Redstart
1-1-
Western Palm Warbler
1-11
Prairie Warbler
12--
Northern Cardinal
---1
Painted Bunting
2111



Today's Banding StatsCaptain SamsLittle BearTOTAL
# Birds Banded
15
12
-
# of Recaptures
7
4
-
# of Species
12
6
-
Effort (net-hours)
150.6
109.2
-
Capture Rate (birds/100 net-hours)
14.6
14.7
-
# of Nets
32
28
-

2025 Fall Cumulative Banding Stats Captain SamsLittle BearTOTAL
# Birds Banded
1,751
1,045
2,796
# of Recaptures
263
241
504
# of Species
54
49
63
Effort (net-hours)
6,292.8
4,226.8
10,519.6
Capture Rate (birds/100 net-hours)
32.0
30.4
31.4
# of Days4134



Banding Staff

Aaron Given (CS)
Liz Held (LB)
Arden Schneider (LB)
Camille Beckwith (LB)
Jeremiah Sullivan (CS)
Amy Nickerson (CS)
Keegan Foster (CS) 



Note:  All banding, marking, and sampling is being conducted under a federally authorized Bird Banding Permit issued by the U.S. Geological Survey’s Bird Banding Lab. 

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