Tag Archives: Bluejay

2021 WILD CREATURES REVIEW! PART TWO

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Cape Ann Wildlife – a year in pictures and stories

July through December continued from part one

July 2021

Conserve Wildlife NJ senior biologist Todd Pover makes a site visit to Cape Ann beaches, summer long updates from “Plover Central,” GHB Killdeer dune family raise a second brood of chicks,  Cape Hedge chick lost after fireworks disturbance and then reunited with Fam, Great Black-backed Gulls are eating our Plover chicks, thousands of Moon Snail collars at Cape Hedge,  Monarchs abound, #savesaltisland, missing Iguana Skittles, and Earwig eating Cecropia Moth cats.

August 2021

New short film for the Sawyer Free Library The Marvelous Magnificent Migrating Monarch!, Coastal Waterbird Conservation Cooperators meeting new short Piping Plover film, Ruby-throated Hummingbirds in the garden, why we love Joe-pye and other wildflowers, butterfly friends, Monarch cats in the garden, what is the purpose of the gold dots found on Monarch chrysalides?,Black Beauty came calling, Tigers in the garden, School Street sunflowers, Hoverflies, luminescent Sea Salps return to Cape Ann beaches, Petal Dancers and lemony Yellow Sulphurs on the wing.

 

September 2021

Flower Fairies, irruptive Green Darner migration, mini glossary of late summer butterflies, what to do if you find a tagged Monarch, Painted Ladies, White-tailed Deer family, Monarchs mating, Tangerine Butterflies,  yellow fellow in the hood, and Beauty on the Wing first ever live screening at the Shalin Liu.

October 2021

Bee-sized butterfly the American Copper, Monarch conga line, Thunder and Cloud, abandoned Piping Plover egg, School Street Sunflowers, Monarchs migrating, quotidian splendor, Monarch fundraiser updates, collecting milkweed seeds, the Differential Grasshopper, Cooper’s Hawk – a conservation success story,  #ploverjoyed, and nor’easter from the EP Lighthouse.

November 2021

Bridges between life and death, ancient oak tree uprooted, autumn harvest for feathered friends, Monarch migration update, we have achieved our fundraising goal!, Harbor Seal pup hauled out,  flight of the Snow Buntings, and a very rare for these parts wandering Wood Stork calls Cape Ann home for a month.

December 2021

New short film Wandering Wood Stork, tiny tender screech owl suffering from rat poison under the care of Cape Ann Wildlife Inc., Praying Mantis in the autumn garden, masked bandits in the hood, short film The Majestic Buck and Beautiful Doe Courtship Frolic, Snowy Owl boy in the dunes, short film Cedar Waxwing vocalization, the story of the Steller’s Sea-Eagle’s foray to Massachusetts, and Harbor Seal Pig Pile.

Steller’s Sea Eagle – Haliaeetus pelagicus

 

 

 

SEE PART ONE, JANUARY THROUGH JUNE, HERE

 

BEAUTY ON THE WING: LIFE STORY OF THE MONARCH BUTTERFLY COMING SOON (FEBRUARY 2022) TO A PBS STATION NEAR YOU!

 

 

 

 

WHY DO BIRDS LAY BLUE EGGS?

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Did you ever wonder why some birds, such as Bluebirds and Robins, lay blue or bluish green eggs? And just as interesting why, in some cases, Bluebirds which generally lay blue eggs, a nest may comprise eggs that are almost white?

The earliest avian eggshells probably lacked color, or pigmentation. Over time, most likely to protect the eggs from predators, birds evolved a diverse range of colored shell markings from mottled brown, gray and beige to rainbow hues from pure white to pale pink, lavender, yellow, aqua, orange, blue, born and even black.

The molecules that cause pigmentation in bird eggs are biliverdin (the blue-green shades) and protoporphyrin (red and brown colors and speckles) but we can talk about blue eggs without getting too technical.

Basically, blue and blue-green strikes a balance between white and very dark colored eggs. Darker eggs are predicted in moderate light to shield the embryo from intense light, including harmful UV radiation. If when eggs are in an exposed nest and the shells are too dark, it can cause the interior to heat up, similar to a “dark car effect.” Simply stated, blue eggs regulate the effects of sunlight on the developing chick (embryo).

This doesn’t explain entirely why Eastern Bluebird eggs range from white to blue green. Many cavity nester’s eggs are white because the adults need to see the eggs in the dark. Wood Ducks are an example of cavity nesters with white eggs. American Robins generally nest in trees or a semi-exposed site and their eggs are blue, affording both protection from dangerous UV light and low risk from heating up. Eastern Bluebirds are cavity nesters but only about 4 to 5 percent of their eggs are white. Oftentimes when learning about a topic, myriad more questions come to mind!

White Eastern Bluebird Eggs

To read more –

https://www.researchgate.net/publication/298798982_Shedding_Light_on_Bird_Egg_Color_Pigment_as_Parasol_and_the_Dark_Car_Effect

https://journals.sagepub.com/doi/abs/10.3184/175815511X13207833399666

In reading about blue eggs I thought readers would enjoy seeing the amazing speckled and pear-shaped brilliant blue egg of the Common Murre, from USFWS

Some birds with blue eggs that nest locally include Red-winged Blackbird, Gray Catbird, Snowy Egret, Great Blue Heron, Little Blue Heron, House Finch, Bluejay, Goldfinch, European Starling, Eastern Bluebird, and American Robin.

American Robin nest at a friend’s home

Both Bluebird nest egg photos courtesy Google image search