There are three new babies in my life. 

While I am definitely happy to report that I became a grandmother last fall, there are other babies that also have my rapt (or raptor) attention. Two are not related to me by blood or marriage, and are not even the same species, yet we follow their growth and chart their milestones almost as intently as our own brood.

Felix Neck’s new spring addition was an osprey cam and over the last few months we have watched bird drama unfolding as the resident pair built, rebuilt, refurbished and remodeled its nest in preparation for the arrival of up to four eggs. In this case, momma bird laid three eggs and incubated them for forty-one days, more than the usual 38 days for typical osprey incubation.

Osprey chicks are semi-precocial and, when they emerge from their eggs, are somewhat independent. These babies can move around, are down covered, and have their eyes open. The chicks can’t fly for their first few months so cannot obtain food, which is almost exclusively fish and are a long way down from their up-high perch. Known as nidicolous, these chicks will stay in the nest for a long time after birth and will be fed and reared by their parents.

For the osprey, babies made four, as one of the eggs did not hatch. Osprey eggs are usually laid in intervals of one to three days apart and the female will begin incubation immediately after she lays her first egg.  The Felix Neck pair again bucked the trend and averaged four days between eggs.

Development within the egg starts as soon as incubation begins so hatching of the clutch will occur sequentially. This chronological appearance of chicks is known as asynchronous hatching, and this birth order may have consequences.

The first chick to emerge will be the largest and strongest, as it will begin eating ahead of its siblings. Eggs usually hatch in intervals of three to five days from the one before, the same interval that they were laid. Interestingly, the Felix Neck pair again did their own thing as both of the successful eggs hatched the same day.

From here on out, it is a competition for food with the first born chicks often getting the most nutrition. When food is not plentiful, the smallest and youngest chicks can perish, dying of starvation while the older ones monopolize food brought by their parents.

When food is abundant, chicks’ growth is extraordinary. Within four hours of hatching, parents will feed them fish, which comprises almost 99 per cent of an osprey’s diet through its lifetime. Chicks begin life weighing about 50 grams, just slightly less than the mass of a golf ball. In the first eight days, the chicks will triple their weight, then double it again in the following four days.

For the next 15 to 30 days, the chicks will put on 40 grams per day, adding two to three per cent of their final body weight every 24 hours. In human terms, my grandson would have to gain four and a half pounds per day to grow at the same rate as osprey chicks.

The osprey offspring will be ready to fledge after 55 days. Soon after, the parents will fly the coop and the juvenile birds will be on their own until they, too, leave the Island to spend a few years in South America before returning to have their own families.

Life is a journey — for osprey, literally so. And while the educators at Felix Neck may look forward to teaching younger generations about these birds, we are also learning what generations of ospreys can teach us.

Suzan Bellincampi is director of the Felix Neck Wildlife Sanctuary in Edgartown, and author of Martha’s Vineyard: A Field Guide to Island Nature and The Nature of Martha’s Vineyard.