River Life!

Common Merganser (female) - Mergus merganser

I had an incredible week of wildlife sightings on the North Yuba River this week!!! In these days of environmental uncertainty, it is with relief and joy that I watch the wildlife return to our river. It is wonderful to see this local ecosystem still intact and thriving! The river has warmed up, the water level is a lot lower, and the flow rate has dropped to 400 cfs. This has made it a lot easier for a variety of fish eaters to catch their prey! 

The Common Mergansers (above) returned a while ago, but their numbers have increased in the past week. They are diving ducks, and hunt underwater for fish, aquatic mollusks, insects, crustaceans, worms, frogs and even some small mammals. They can stay underwater for up to two minutes! Their bills are serrated for grabbing slippery prey. The females nest primarily in tree cavities made by woodpeckers! I haven't seen any baby ducks this year. However, merganser eggs have been known to hatch as late as the end of July, so we may still see some ducklings!

Mink (female with 3 young) - Neovision vision

We were on the river one morning this week, when I noticed some movement in the Indian Rhubarb plants on the opposite shore.  To my absolute delight, it was a female Mink with 3 young!!!  WOW!!!  They were moving really fast upstream, in a compact group along the edge of the river.  They would occasionally scramble up on the rock slabs, rustle through the bushes, and then re-enter the river!  We got to watch them for almost 4 minutes!  They eventually crossed the river and swam out of sight.   It was so incredibly amazing!!!  This is first time, in the 32 years I've lived here, that I've seen Mink!  It was such a pleasure to watch these incredible wild animals swim past!  A few days later I saw one very distant River Otter swim across the river with a fish in its mouth!!  WOW!!!  I live in paradise!

Mink (female with 2 young) - Neovision vision

The young Mink weren't newborns.  They were about half the size of their mother, and probably several months old. These young mink will stay with their mother for 6-12 months.  They will then split off to start their own families.  I have never seen live Mink before!!! How exciting!

Mink (female with 3 young) - Neovision vision

If you see a group or pair of Mink together, it is usually a mother with offspring.  Adult male and female Mink, do not stay together.  They only come together briefly to mate.  The female alone raises the pups.

Gray Fox with young kit! - Uryocyon cinereoargenteus

The morning after I saw the River Otters I went back to the same area, hoping to see them again.  I didn't see any otters, but I saw some movement on the opposite shaded bank.  I zoomed in with my camera and was totally astounded to see a Gray Fox with 2 young kits!  WOW!!!  The kits were so cute!  They moved off quickly into the shade, where they were really camouflaged and hard to photograph.  I was able to watch them for a minute or so, until they disappeared into the brush.  These young kits will stay with their parents for approximately 10 months.  Gray Foxes mate for life, and both parents raise the kits!  

Two Gray Fox kits - Uryocyon cinereoargenteus

From a distance, the young foxes looked like young Mountain Lions, 

with their long tails and rounded ears!

Spotted Sandpiper - Actitis macularius

Every year a few Spotted Sandpipers return from their winter grounds in the southern U.S. or South America, to our section of the river to breed and raise their young.  I spotted one along the shore just this week!  The females sometimes practice polyandry, and will breed with more than one male.  The males will incubate the eggs and feed the young after they hatch!  In the meantime, the female defends the breeding/nesting territory from predators and other sandpipers!  Last year I was lucky enough to see two fledgling sandpipers!  Maybe I'll see some this year as well!

Belted Kingfisher (female) - Megaceryle alcyon

For many months, I haven't seen or heard a Belted Kingfisher on the river.  Luckily I spotted this female a week ago flying down river.  She stopped and checked me out  from a dead branch for a few seconds, before taking off again.  I've seen and heard one several more times since then.  Kingfishers catch prey by diving from perches into the water.  They eat small fish, crayfish, bullfrogs, tadpoles and insects.  Most fish are caught in shallow water or near the surface, usually no deeper than 60 cm.  Clear water and an unobstructed view of prey are essential for successful foraging.  Since they grab prey with their bill, they do not usually submerge.  They regurgitate pellets of undigested fish bones and exoskeletons!  

Great Blue Heron - Ardea herodias

There has always been at least one Great Blue Heron year-round on our section of the North Yuba River.  However, I haven't seen one for months, probably due to the late occurrence of Summer weather and the extremely wet Spring.  Just this week, one has shown up!  I've seen it on the river the past two mornings.  They are large birds, measuring 4' tall, with a wingspan of 7'!  Their method of hunting is to stand motionless in running water, wait for prey to go by, and grab them with their bill.  They will quickly eat fish, frogs, crayfish, aquatic insects, and even ducklings.  They regurgitate pellets of undigested hair, but can digest fish bones.

  

Osprey - Pandion haliaetus

Last summer there was an Osprey that frequented our section of the river for months.  I took tons of photos of it during that time.  It was so fun!  Just this week, I spotted an Osprey on the river!  I'll never know if it's the same one as last year, but it could be!  Ospreys overwinter in the fish-rich coastal areas of southern California and Mexico, as well as the, coast, lakes, and rivers of South America.  In the spring, they fly north to breed, mainly in Alaska and Canada.  Ospreys are the only raptors that dive feet first to catch fish.  Fish are 99% of their diet!  Last year I saw one flying with a fish in its talons, as well as one diving into the river!

Blue Dasher Dragonfly - Widow Skimmer Dragonfly

Pachydiplax longipennis - Libellula luctuosa

Dragonflies!

Dragonflies are as much a part of our river as River Otters and birds!  In the late afternoon, I like to go down to the river and watch the dragonflies glinting in the sun.  Sometimes there are hundreds of them!  They are incredible flyers, and can hover, zoom forward, and even fly backwards!  Dragonflies catch other flying insects with their legs, while flying.  They also consume their prey while in the air!  They lay their eggs in or near slow-moving water, often on plants. The eggs hatch into nymphs that live underwater for up to several years, depending upon the species!

Four-spotted Skimmer - Western Meadowhawk Dragonfly

Pachydiplax longipennis - Sympetrum occidentale

Northern Pacific Rattlesnake - Crotalus oreganus ssp. oreganus

Reptile Weather!

Reptiles are ectotherms, and are dependent on external sources to maintain their body heat. To regulate their body heat they will bask in the sun when it's cool, and hide in the shade when it's too hot. With the hot temperatures we've been having, I've been wondering if snakes would be out during the day. It turns out that extremely hot temperatures can kill a snake within 10-20 minutes. So when the air temperature reaches the high 90's and into the 100's, snakes seek out shade and wait for the temperature to drop.  We spotted the Northern Pacific Rattlesnake (above) on our property this week!  Although rattlesnake bites are not usually deadly for humans, they can be fatal for pets.  We have a small dog, so we hosed this snake and it quickly scooted off our property and went back toward the creek.   

Its rattle had 8 segments. Rattlesnakes create a new segment on their rattle every time they shed their skin. Snakes shed their skin more than once a year when young, and less than once a year when old, so the number of segments in a rattle does not indicate their age. Additionally, segments can get broken off during a snake's lifetime.  Most Northern Pacific Rattlesnakes are active from dusk to dawn, looking for prey!  They eat birds, lizards, snakes, frogs, insects, and small mammals, including mice, rats, rabbits, hares, and ground squirrels. 

Spiny Lizard (?) - Sceloperus sp.

Lizards seem to be everywhere these days!  I photographed these three lizards down by our garden.  I'm not a herpetologist, so I'm just guessing what kind of lizards they are.  The website www.californiaherps.com is a great resource for identification of herptiles (reptiles and amphibians).  Even so, I still find it difficult to identify some lizards!  Apparently their colors can change with temperature changes!

Spiny Lizard (?) - Sceloperus sp.

Is this a female?  Let me know if you know!

Northwestern Fence Lizard - Sceloperus occidentalis occidentalis

The following information is from www.californiaherps.com.

"These lizards are diurnal. Often seen basking in the sun on rocks, downed logs, trees, fences, and walls. Prefers open sunny areas. Active when temperatures are warm, becomes inactive during periods of extreme heat or cold, when they shelter in crevices and burrows, or under rocks, boards, tree bark, etc. Found in a wide variety of open, sunny habitats, including woodlands, grasslands, scrub, chaparral, forests, along waterways, suburban dwellings, where there are suitable basking and perching sites, including fences, walls, woodpiles, piles of rocks and rocky outcrops, dead and downed trees, wood rat nests, road berms, and open trail edges. Common and easily encountered in the right habitat. This is probably the species of lizard most often seen in the state due to its abundance in and near populated areas and its conspicuous behavior."

 I photographed this Black Bear in the river last year!  

I haven't seen any bears yet this year.  Where are they?

What's happening in the Lakes Basin?

What insects are out there?

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

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