River Birds!

Spotted Sandpiper (fledgling) - Actitis macularius

About three weeks ago I spotted this fluffy, fledgling Spotted Sandpiper "teetering" (holding head low while tail-end vigorously bobs up and down) on the river's edge!  I've been watching it, and several other fledglings, mature over the past 21 days.  Sandpiper chicks are born precocial and are able to walk and feed within their first 2 hours!  They start teetering 30 minutes after they're born, and can fly within 18 days!  They feed on midges, mayflies, grasshoppers, flies, crickets, beetles, caterpillars, worms, mollusks and crustaceans, fish and spiders.  They will forage for these invertebrates in rivers, creeks, ponds, and lakes, as well as on dry land.  When first born they are covered in downy feathers, which molt over the next 3 weeks as their adult feathers emerge.  Right now they are considered "juveniles" and have lost their fluffy, downy feathers.  They won't acquire their spotted breast feathers until the mating season begins next Spring.  

Spotted Sandpiper (juvenile & breeding adult) - Actitis macularius

Spotted Sandpipers are the only shorebird found commonly in the Sierra, from the foothills to timberline. Starting in July, Spotted Sandpipers migrate singly or in small groups to their wintering grounds, which extend from the extreme southern United States to southern South America. The adults leave before the juveniles. I guess the local juveniles will be leaving soon. It has been fascinating and fun to observe them!

Common Merganser  (juveniles & adult female) - Mergus merganser

The Common Mergansers on our river are numerous!  In addition to the two females and their young, that I first observed more than a month ago, several more females and their young have arrived.  The young are born precocial and can swim and catch their own prey within a day after their birth. They begin to dive after 2 days and are proficient divers after 8 days.  They are primarily fish eaters, and have nictitating membranes on their eyes, that work like goggles underwater.  In fact, just this morning, I watched a juvenile catch a fish in the river!  They will also eat aquatic mollusks, crustaceans, insects, worms, frogs, small mammals, and plants.  It takes about 65-75 days for all of their adult feathers to emerge, and they are able to fly.  They will migrate in October to their over-wintering grounds in central or southern California, Arizona, Nevada, or Utah.

Common Merganser (8 juveniles & adult female) - Mergus merganser

I think this is the Merganser that had 16 ducklings when I first saw her 6 weeks ago.  Right now she has 8 ducklings, and they are getting big fast!  Some of the ducklings may have gone off with a different female, or were eaten by minks, otters, foxes, or herons.  It's tough out there in the wild!

Canada Geese  (juvenile & adults) - Branta canadensis

I've seen two pairs of Canada Geese in our neighborhood this year.  Initially both pairs had two fledglings, however one of the fledglings is gone.  It was probably preyed upon by a Grey Fox, or Pine Marten when it was little.  The goslings will stay with their parents for their first year.  Whenever I see them, the parents are in close proximity to their young.  The young geese are born precocial and are able to walk, feed, swim, and dive within 24 hours.  They feed mainly on grasses, sedges, and aquatic plants in the summer, grains and berries in the winter.  They may stay here all winter if the weather is mild, or they may migrate down to California's Central Valley if it's too snowy.  

Canada Geese  (juveniles & adults) - Branta canadensis

It takes approximately 65-75 days for the goslings to acquire their adult size and feathers.  However, it seems like they get big fast!  Currently they are lot bigger than they were when I took this photo a few weeks ago, and are almost full grown.

Osprey (adult) - Pandion haliaetus

Recently Returned!

For months I haven't seen a Great Blue Heron, Belted Kingfisher, or Osprey on our section of the river.  Just this week they have all shown up in their regular locations!  They are all big eaters of fish, so perhaps the lower water level is making it easier to catch the trout.  I don't know if they are the same individuals that I've seen year after year, but it feels like they are.  Especially when they perch on the exact same tree or branch as before! The Osprey pictured above was eating a fish when I saw it, and a Raven was perched one branch below the Osprey!  The Raven flew off before I could get a photo.  I'll bet that it was hanging out hoping the Osprey would drop the fish!  Wow!  

 

Great Blue Heron (adult) - Ardea herodius

The Great Blue Heron is the largest bird in our area, with a wingspan of  72" and a length of 46".  In comparison, an Osprey has a wingspan of  63" and a length of  23".

Belted Kingfisher (female) - Megaceryl alcyon

I've written about these birds several times in previous blogs.  Use the "Search this Blog" tool on the top right of the page to find the information you're interested in.  Let me know if it works!  

Whatever the reason is for their return, it is a joy to see these beautiful birds again!

The answer is "NO!"  Banana Slugs lay gelatinous eggs, from which the baby banana slugs are born.  They do NOT have live births!  The baby banana slugs are capable of feeding and moving as soon as they emerge from the egg.  Does this make them "precocial"?

What's happening in the Lakes Basin?

Are the bears still around?

Are there any wildflowers left or have they all dried up?

Check back next week for the answers to these questions and more!

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