A Molt is Pretty Marvelous
By Gail Cochrane
Liberty Wildlife Volunteer
Feathers, those remarkable instruments of flight, insulation and beauty, do not last forever. They fray and break down, wearing with use and exposure to the elements. So, birds must replace them and do so with annual or biannual molts.
Molting happens when hormonal changes are brought on by the seasons, and allows birds to exchange worn feathers for shiny new ones that offer greater performance. This happens gradually over several weeks as birds must continue to stay warm and find food while also expending the energy to grow in a new supply of feathers. The frequency and timing of molting varies by species and by the climate of their habitat, but some generalizations can be made.
The Cornell Lab of Ornithology identifies several categories of molting behavior. Species including hawks, owls, woodpeckers, hummingbirds, flycatchers and thrushes have one complete molt per year, when they replace all of their feathers. These birds’ appearance are the same year around.
Birds such as warblers and tanagers have one complete molt, plus one “pre-nuptial” molt where only body feathers are exchanged. Males in particular don brighter, bolder colors for breeding season. The complete molt takes place after breeding season and before migration. Gambel’s quails fall into this group, although quails only exchange a limited number of body feathers in the early spring prenuptial molt.
Birds that live in areas where their plumage takes a lot of wear and tear have two complete molts per year. Marsh wrens and bobolinks encounter harsh vegetation as they forage, and require two molts.
Young birds are identifiable by their immature feathers. Passerines, or perching birds, hatch naked and grown their first feathers or juvenal plumage in their first few weeks. Nonpasserines hatch with a natal down covering their bodies. These downs are replaced by juvenal plumage in what’s termed a postnatal molt. Most passerines come into their adult plumage or definitive plumage around one year of age.
Larger birds do not reach plumage maturity for two years or more. Gulls and eagles take the longest, with complex stages of molting and plumage coloration. Gulls generally acquire definitive plumage at four years and bald eagles at five to six years.
The American Kestrel is one of the only birds of prey that exhibits sexual dimorphism, and is unique in that nearly adult-like plumage is attained prior to fledging. Thus, the males and females of this species can be identified early on, due to the coloration of their feathers. Kestrels have an incomplete molt in the fall of their first year, but retain feathers in their wings and tail and parts of their bodies until the second and complete molt the following year. By winter of their second year, the young falcons have attained their definitive plumage.
(female kestrel) (male kestrel)
By: Carol Suits
Liberty Wildlife Volunteer
The Liberty Wildlife Superhero Club and the new Nature Explorer Club meet September 16th. More information below!
Kid Stuff does a flash-back to the 2022/2023 Superhero Club activities
1. 2. 3.
- Checking out a booth on our field trip to the OdySea Conservation Expo
- Everyone made a nature journal to record their experiences
- The “Partner Pals” activity needed signs made to hang next to their Ambassador Pal
- Out on the river trail, we got help from our “Litter Critters” partner
- Superheroes helped keep the Salt River trail clear of litter
Join a Liberty Wildlife Kids’ Program
New for this year
Explore nature’s wonders through meaningful and fun activities!
Be a Superhero!
Grades 1 – 3 8:30 – 9:30
Visit with our animal Ambassadors
Listen, explore, and learn about nature
Be a Nature Explorer!
Grades 4 – 6 10:00 – 12:00
Explore ways to help wildlife
Participate in hands-on activities to make a difference
Meetings are usually the third Saturday each month starting in September.
Classes are limited to 10 participants.
Sign up now for fall sessions
Write, call or text
Some fun with a game video and puzzles.
https://www.youtube.com/watch?v=SrVMemjoBic – This is an animal sounds game.
I played it and maybe got 5 or 6 of them right. (The cow was easy.) Check out the panda sounds!
Meet Another Education Ambassador
By Claudia Kirscher
Liberty Wildlife Volunteer
Zelda is a Gray Hawk, a Mexican tropical species found only in Mexico, southern Arizona, and New Mexico border. They are summer residents in Arizona, wintering in Mexico.
This is a medium-sized buteo with short rounded wings and black and white banded tail. Juveniles have dark brown backs with heavy brown streaks and spots on the front. Adults are pale gray with finely barred chests. Females are noticeably larger. They have a distinctive 3-note whistle call.
These hawks prefer scrub woodlands, forest edges, and clearings near riparian areas. Diet is mostly lizards but also birds, small rabbits, ground squirrels, and large insects.
Zelda was hatched in 2022, coming to us in early 2023. She was still in her juvenile plumage but has been gradually transitioning into her adult plumage over this her second calendar year. (See photos). She was found in SE Arizona and is nonreleasable due to head trauma and left eye injury secondary to being struck by a car (most likely).
Come on down to visit, hear her story, and see her remarkable transition to adult plumage!