Age and sex ID based on molt, part 2

First fall immature Ruby-crowned Kinglet, Central Park, NYC, October 8th

Click on the image to get a larger view of this bird (and ignore the fact that the © statement is floating in mid-air). This is a pretty classical example of retrix (tail) and primary (wing) feather shape in a first fall immature - the feathers are somewhat pointed and in fact in this bird the feathers come to a sharp point. Adults have blunt and rounded ends to their feathers. At this time of year, when both adults and immatures have relatively recently molted their flight feathers as well as their body feathers, all of the plumages look pretty fresh. If I ever get an adult Kinglet to pose for me - these are especially frenetic birds - I shall put one up for comparison.

I'm not sure there's any meaningful plumage difference between sexes at this stage, so I'm not even going to try.

Age and sex ID based on molt, part 1

I take a lot of photographs, and some of the birds I take photos of are as much for plumage interest as aesthetics.  This is an example of a somewhat scruffy Red-winged Blackbird at Brigantine NWR in NJ in August:

Blackbirds go through active molt in August-September and frequently look quite odd.  This particular RWBL has molted some body feathers but not yet the head or neck, so it looks odd in the head.  If we zoom in on the tail:

it is heavily frayed - older feathers not recently molted.
On the wings there's a mix of mostly new flight feathers and one or two older ones:

Looking at the condition and overall coloration of the feathers tells us all we need to determine age and sex, within reasonable bounds.  The feathers on the tail are quite worn, so they are quite a few months old - molted at or around this time last year.  So this bird is an adult, i.e. more than one year old.  Similarly that outermost primary looks pretty worn too.  Since this bird is an adult, the fact that the feathers are brown means that it must be a female - there is no distinct "first summer" plumage for male RWBL birds so a male of this age would have black flight feathers.  In fact the pointedness of that worn outermost primary suggests that this adult female might be only a little more than one year old - flight feathers from first fall passerines are usually more pointed than adults.

Barnegat Inlet, March 21st

Overcoming some inherent sloth I headed for Barnegat Inlet on the morning of March 21st. Getting there at a slightly tardy 8am I still managed to be only the second one out on the breakwater in relatively balmy conditions with a moderate breeze from the south.....and found just the usual suspects on the falling tide.

There appeared to be a diminishing number of sea ducks although this could just be day to day variation. While the numbers of Long-tailed Ducks were high, and engaged in mating displays in tightly-knitted flocks, I only saw two scoters (a pair of Black Scoter) and a few Common Eiders. Harlequin Ducks were present in moderate numbers. The bird(s) of the day were three Northern Gannets headed south off the end of the breakwater. Other birds included Dunlin, Black-bellied Plover, Common Loon and a single Red-throated Loon, Brant, one Red-breasted Merganser and an Ipswich-like Savannah Sparrow.

All of the Common Loons I saw were in pre-alternate molt, with one apparently already in full alternate (breeding) plumage. Some Long-tailed Duck were in pre-alternate molt although most still seemed at or close to basic plumage and I didn't see any obvious full alternate plumages. Looks like it will be soon, however.