So what's been happening with the island's shrikes?
Well, we are now to the point where every fledgling has reached independant status. In the 1990's, there were only 14 San Clemente Loggerhead Shrikes. As of the other day, adults and hatch-years combined, the island has over 170 known LOSH.
That number will go down in the coming months.
Still, not too bad, eh?
The shrikes are all pretty much in post-breeding dispersal.
After the adult pairs are finished nesting, egg-laying, incubating, caring for nestlings, and caring for fledglings and all other parental duties at the natal sites... the birds peace out to parts unknown.
Generally the adults split up, the fledglings(hatch-years) are now independant and must fend for themselves and biologists scatter to find out which birds are where, who's alive and who is not, etc.
One important exercise we have been up to recently is trapping unbanded Hatch-Years. During the course of the breeding season there have been nests that we could not reach in order to band nestlings. There have been a few nests that we have just flat out overlooked. There are also areas that we are not allowed into. With these shrikes nesting in the canyons(you guys have seen some pics) one can understand how having some unbanded Hatch-Years around the island is possible. 
The trap we use was a new design to me so I was and certainly still am eager to help trap "--/-- HY" when one is found.
The trap (Santolo), made of a mesh hardware cloth, has a small compartment in the bottom, which we occupy with a mouse. The mouse is actually protected from the shrike as there is the mesh "floor" above its little holding cell.
There is then a door/lid on the top of the trap which is propped open. A dowel rod, or even a conveniently sized twig is attached and put within the trap, below the door and ceiling. It acts as a perch and then the trigger mechanism that closes the door/lid on the bird.
It's incredible to observe very well, just how far these birds can notice movement of a prized, choice, mouse scurrying around in a small square cell. Perhaps one day I will have the presence of mind, and luck of finding a "--/-- HY" that cooperates, while I have a camera set in "movie mode" and document with motion how this methodolgy works. For the moment, a few still shots taken by a co-worker.
It often takes the shrike a little while to find the entrance in order to get closer to this convenient prey-item. So the bird will go toward the trap from different sides. Hovering about, it hopefully, and does often enough, find the opening at the top and drops down to that dowel rod perch, near the mouse. Lid closes. Shrike isn't too happy about it. We sprint to the trap to extract the bird before it has the chance to even remotely injure itself. The bird is then put into a "bird bag" and it calms down a degree or two.We work this bird as we would any other nestling that I have described in previous posts. A color band combination and metal service band, both to be unique to that individual bird is selected. The bird is weighed, feather samples taken for DNA analysis, etc.
Remember shrikes have a beak that is specially designed to quickly sever the spines of their prey. They also like to chew off color bands. Do to that affinity, we continue to heat seal the color bands with a butane-fuel torch iron as seen below.
This biologist is particularly talented with this instrument.
Having a bird in hand is always an excellent chance to check out the feather tracts. Due to wear-and-tear, the molting of feathers, and other happenings, one can age a bird more easily. Now obviously, this is a HY bird, i.e. within year # 1 of its life, but knowing that helps reinforce what the feather tracts are to look like this time of year in a bird hatched this year. Here are some pics...
Say hello to 2008 Hatch Year, origin Unknown, Green-Service/Blue-White. Or just GS/BW.
GS/BW and some guy.
peace and good evening,
MWYork
**photos by M. C. Cammarota
