While this post has absolutely nothing to do with my writing, it is something that means a lot to me. I've been watching the nesting efforts of Green Herons at a pond next to our house for almost two months now, and although I have no scientific credentials whatsoever and am by no means an authority or even a pretender to any kind of knowledge of any kind, I have wanted to document some of my observations.
|Second Brood - One Unhatched Egg|
So, enough with that.
I noticed the first clutch or brood of Green Herons, Butorides virescens, on June 17, 2018. I saw a juvenile bird that still had down on its head, hanging around the pond. By June 19, I'd seen five juveniles, crowding around an adult and begging to be fed.
Before that, I'd seen adult Green Herons hanging around the dock and pond, and had watched a male adult calling from one of the pilings of the dock.
Unfortunately, by the time I observed the five juveniles, they were already out of the nest and exploring the tangle of vines and trees around the pond.
To my surprise, on July 3, 2018, I saw a new nest in a sweet bay bush overhanging the pond. There were 3 downy juveniles in the nest. I don't know if this was the same pair of adults re-nesting or if it was a second pair of adults. I suspect it was a second pair of adults since there would have had to be too much overlap between the feeding of the first set of juveniles and the activity involved in sitting on the nest for the 2nd brood, given the dates.
The second set of juveniles have allowed me to gather photographs and record the early life-cycle and activities of Green Herons. So the following is the information I've collected between the two sets of juveniles. I did, unfortunately, miss a 7 day period with the second set of juveniles, but it was unavoidable.
Although I didn't witness the actual mating behavior, I noted that by April 20, 2018, a male adult
|Male Heron - Preparing to call|
Since I first noticed juvenile Green Herons (the first clutch of five chicks) with down on their heads exploring the area around the pond on June 17, 2018, I concluded that the first nest must have been built around May 10, give or take a few days. This date was calculated based upon an incubation period of 19-21 days, and the beginnings of exploratory behavior in chicks about 15 - 21 days old. Note that all these dates are approximate. I figured that the first batch of Green Herons hatched around June 1, 2018, give or take a few days.
|Second Nest - Unhatched Egg Lower Right|
|Chicks on July 3, 2018 When First Observed|
Since I was only able to observe fairly recently hatched chicks in the second clutch (the first being too well concealed to observe), I'll start with them.
July 3, 2018 - 2nd clutch
|Three Chicks in Second Brood|
Based upon the available literature, the chicks were most likely somewhere around 6-8 days old at this point, so they may have hatched sometime around June 26 or so. They were all covered with grayish-white down.
Over the next couple of days, the chicks mostly stayed in or very close to the nest, but they were already interested in exploring. One chick nibbled at a nearby twig in exploratory behavior.
July 6, 2018
|Feathers Starting to Push Out Down|
July 9, 2018
|July 9 - Feathers Developing|
July 18, 2018
|Juvenile from 2nd Brood - Just a little down on head (30+ days old)|
We now pick up development from my observations of the first brood, since this development is still in the future for the 2nd brood...
21 Days Old
By the time the juveniles were 21 days old, they were making short flights and leaping around the shrubbery around our pond. I noticed one juvenile dipping twigs into the pond to lure small fish into striking distance (Green Herons are one of the few tool-using birds).
|1st Brood Juvenile Returning to Nest Area (Age 60+ days old)|
32 Days Old+
By the time the juveniles were around 32 days old (by June 23, 2018 for the first clutch), they were really exploring the entire area. They flew to the dock and the yard, as well as down to the small beaches nearby. While the adults continued to visit, I didn't see them feed any of the juveniles, although the juveniles still mobbed them when they arrived.
35 Days Old+
|Juvenile Preening - (Age 35+ days)|
Over the next few days, the juveniles continued to fly to nearby salt marshes to forage during the day, but they usually returned in the evening.
By the time they were around 40 days old, they were pretty well dispersed. Some of the juveniles from the first clutch still returned to the pond, however. One day, three returned and took up positions on a perch they favored while "growing up."
|3 Juveniles from 1st Brood Before They Dispersed|
The second brood was not as successful. Out of four eggs, one did not hatch, and one chick appears to have died at around two weeks. The other two juveniles are still thriving, however they have not fully fledged yet. They still have down on their heads and are making short flights/leaps around the trees surrounding the pond. The adults are still feeding them, as well.