Build your own website. Do it yourself websites.


Painted Lady Butterfly Phenomenon
Category: Birding at the Chico
 Painted Lady butterflies were common to abundant this spring on Chico Basin Ranch. They seem to disappear in the fall, however this year they are abundant.  Radar images show why Painted Ladies aren't seen most falls in a migration that extends further north (arctic) and further south than the famous monarch butterfly migration. The combined spring and fall Painted Lady migration (fall butterflies are the offspring of spring Painted Ladies) is as long as 9000 miles in length. Sophisticated radar now shows Painted Ladies migrate as high as 3,000 feet above ground level and can fly up to 30 mph. Due to abundant summer rains on Chico Basin Ranch, the common rabbitbrush scrub (Ericameria nauseosa) has produced a bumper crop of flowers and migrant Painted Ladies are stopping to feed all along Colorado’s Front Range this fall.  Painted Ladies undergo a complete metamorphosis; a life cycle from egg, larva, chrysalis to adult takes about 30 days, meaning the adult butterflies observed in spring migration are not the same individuals seen flying south this fall.  It is not uncommon to see 20 or more Painted Ladies feeding on a single blooming rabbitbrush shrub. 
Posted by Bill M. at 11:47:58 AM

Double-crested Cormorants
Category: Birding at the Chico
 Named for head feathers appearing during breeding season, Double-crested Cormorants were adversely affected after WWII when the use of DDT was permissible as a pesticide. DDT, when broken down to DDE, causes egg shell thinning in birds at the end of the food chain so Osprey, Bald Eagles, and cormorants had difficulty producing offspring because when they incubated their eggs, the shells were not strong enough to support the weight of an adult bird.  Today, this species and others affected by DDT have rebounded from pre-1970 lows and in areas of aquaculture where catfish and baitfish are raised in ponds and in sport fishing areas in the upper Midwest; cormorants are considered villains, congregating in these areas during winter months. In Shakespeare’s plays he uses the word ‘cormorant’ to mean villainous.  Interestingly, both U.S. pelican species eat more fish per day than cormorants do, but because of pelican’s beauty, or possible because of white vs. black plumage, cormorants are considered foes.

In the northeast, cormorants have rebounded so much that people petitioned the U.S. Fish and Wildlife Service to open hunting seasons to reduce cormorant numbers where nesting cormorants’ guano has begun to kill trees at nesting sites and in areas where they were blamed for the drop in bluefish numbers. Cormorants focus on the smaller schooling “trash fish” and eat about one pound per day. In 24 states, aquaculture producers may now shoot cormorants feeding on private ponds or they can call on government officials to shoot birds on nearby roosts and/or oil cormorant eggs. As a result, about 40,000 cormorants are killed each year or about 2 percent of North America’s population in spite of an outcry by the National Audubon Association and animal rights groups.

In Colorado, Double-crested Cormorants nest in small colonies, like the ones at the west end of Pueblo Reservoir, and they are still considered uncommon on the Chico and in neighboring areas. This is a single Double-crested Cormorant on Chico Basin Ranch’s Upper Twin Pond. It is a young bird who was perched on a wooden post drying it feathers. Because of the nature of cormorant feathers, they have fewer oils than waterfowl feathers, so they must air-dry their feathers periodically or they will become waterlogged and sink.

As one Minnesota wildlife biologist summed up the situation in areas where cormorants are abundant…“at the heart of the issue is a nearly zero tolerance for cormorants.” 

Posted by Bill M. on 10/19/2017

Western (Prairie) Rattlesnake
Category: Birding at the Chico

The more common of the two poisonous Colorado rattlesnakes, the western or prairie rattlesnake (Crotalus viridus) is found across the Great Plains.  The other poisonous Colorado snake is the small and very local Massasauga (Sistrurus catenatus). Seven to eight thousand people are bitten by rattlesnakes each year but death from a snake bite in the U.S. is usually about five persons per year. Snake bites in humans are mostly from two rattlesnake species not occurring in Colorado, eastern diamondback and western diamondback.  However, on October 7 of this year a 31-year-old man was bitten on the ankle near Golden, Colorado and he died from the venomous bite. Rattlesnake venom contains both a hemotoxin (affects the blood) and a neurotoxin (affects the nervous system) and the amount injected is usually 20% to 55% of a snake’s stored venom; but a rattlesnake can give a dry bite up to 20% of the time.

Prairie rattlesnakes are viviparous meaning they give to birth to live young, usually in late August into September so it is not uncommon to see young-of-the-year on dirt roads during this time period like the one in this photograph. In October, or sometimes into November, prairie rattlesnakes move to burrows to overwinter, often with over one hundred other snakes including other snake species. If available, rattlesnakes often use prairie-dog burrows in which to spend winter months.

The number of rattles on a rattlesnake shouldn’t be used to age a rattlesnake as they produce a new one every time they shed their skin which is usually at least twice a year if the food source is abundant. In Colorado, prairie rattlesnakes eat a lot of field mice and rodents as large as a small prairie dog and small prairie cottontails, but lizards, voles, and shrews are also commonly consumed.

Rattlesnake meat can be consumed by man but on the Chico prairie rattlesnakes are hunted by raptors like this Red-tailed Hawk whose bare legs are usually not, but sometimes susceptible to a bite from a rattlesnake. Woodrats, found in draws with cholla cactus, are immune to rattlesnake venom and will bite back when attacked by a rattlesnake. It is best to leave rattlesnakes to the hawks. 
Posted by Bill M. on 10/17/2017

A Pandemonium of Trumpets, Croaks, Rattles, and Cries
Category: Birding at the Chico
 Some of our most majestic flying birds, Sandhill Cranes, are common in fall migration at both Chico Basin Ranch and in the San Luis Valley where in spring an annual crane festival highlights this incredible bird.  Two populations occur in migration, Greater Sandhill Cranes breed in the Rocky Mountain regions whereas Lesser Sandhill Cranes migrate east across the Bering Strait before heading south where some join Greater Sandhills flying over Colorado.  The naturalist, Aldo Leopold, described approaching and calling Sandhill Crane flocks as first "a tinkling of little bells" and as they fly closer as "the baying of some sweet-throated hound" and finally when closely overhead as "a pandemonium of trumpets, croaks, rattles, and cries." During clear weather migration Sandhill Cranes can fly high over the Rocky Mountains, but each evening they land in large flocks in marshy areas or in stubble fields and feast on corn and other grains. Because of their fondness for corn, a chemical has been developed to add to corn kernels before they are planted which remarkably keeps these huge migrant flocks feeding on other seeds in the corn fields but not on corn itself. 

Sandhill Cranes are monogamous and they remain paired throughout the year staying a pair until one bird dies. Newly formed pairs join in elaborate dancing before pairing. A brief description of part of their courtship display follows. One member of the pair elevates its bill, arching slightly forward and emits a low purring call. The mate reciprocates. One of the pair then circles the other with wings flapping and the male jumps on the female's back. The male then jumps forward over his mate's head, begins a threat display, and then both enter into a long sequence of  preening. Fun to watch at any of the spring crane festivals in New Mexico, Colorado, and Nebraska. 
Posted by Bill M. on 10/09/2017

Broad-winged Hawk
Category: Birding at the Chico
 A small Buteo with broad wings and a raptor that doesn't breed in Colorado, at least three Broad-winged Hawks were observed the first week of October on Chico Basin Ranch, this one perched at the north side of Rose Pond.  This is usually a secretive eastern forest species that also breeds west into western Canada.  Although solitary during the breeding season, they amass in great numbers on both their spring and fall migrations. Because they avoid flying over large bodies of water, in fall most of the population flies west across Louisiana and the Coastal Bend of Texas before heading south along the west side of the Gulf of Mexico. The daily record of counted Broad-winged Hawk at Corpus Christi, TX, was 446,000 birds. Most of the world population can be viewed at hawk watch sites in Veracruz, Mexico where over 500,000 have been recorded in one day. A few, mostly young birds winter in South Florida. 

It is thought that Broad-winged Hawks are expanding their breeding range to the west and a few have bred in the past in Colorado.  This perched bird can be identified by the short folded wings that are much shorter than the tail, the facial pattern showing a white chin with a dark central vertical streak, and a dark bar on the sides of the brown auriculars and in juveniles,  like this bird, a white supercilium above the eye. 
Posted by Bill M. on 10/08/2017

Chico Fall Bird Banding Seasonal Report
Category: Birding at the Chico
 The fall bird banding season is over, sad but true. This season produced the usual birding excitement and some drama with three different bird banders at different times anchoring the team. The best bird was one that didn't get caught, what will become the first Colorado record of Tropical Kingbird discovered very close to the banding station nets by a 17-year-old and his two younger brothers.  Although the eastern species, Baltimore Oriole, makes an annual appearance at Chico, the one banded was Chico's first ever. Even better, Chico's first record, and therefore, the fist ever banded here, Pacific Wren was measured, studied, photographed from multiple angles and high-fives were given between the few of us in attendance after it was released back into the wild. The second ever Chico Yellow-bellied Flycatcher was also caught, but because of the difficulty in the identification of flycatchers in the Empidonax genus the bander thought it best not to put a metal band on the cool little flycatcher. Measurements and photographic documentation proved the bird to be what we thought it was, one of the few confirmed records of this species in Colorado.  

Rain necessitated the nets to be closed on three days but still the total number of birds banded was a respectable 911 representing 60 bird species and two additional distinct subspecies.  Also exciting was the strong influx of mountain species indicating a lack of food in some neighboring mountain regions. Every season is different and I am already looking forward to the late April beginning of the next Chico banding season.

Posted by Bill M. on 10/07/2017

A Closer Look
Category: Birding at the Chico
 Home to cattle, cowgirls, cowboys, birds, fishes, horses and on occasion goats, sheep and chickens, there is another, hidden side of the Chico Basin Ranch that you have to get down on your knees to see.  Over 300 insect species have been identified here to date and that is only a beginning. If I was still a biology teacher, I would bring all of my classes to the Chico in order to take a closer look.                  

While waking in Chico Basin Ranch’s northeastern most pasture with Maddie and Richard, looking at migrant flocks of Chestnut-collared Longspurs (one of the few bird species endemic to the Great Plains), I heard the distinctive buzz of a robber fly. Robber flies are the wolves of the insect world, swift flying, winged predators. Some robber flies are mimics, looking very similar to bumblebees. This large, drab robber fly, however, has large bulbous claspers on its posterior identifying it as a male in the genus Efferia.  It landed near me and it wasn’t until I returned home to look at my photographs that I saw why the robber fly was spending so much time in one location.  It was sucking the body fluids out of a leafhopper. There are over 2500 leafhopper species in North America. Leafhoppers and close relatives, sharpshooters, use their mouthparts to extract fluids from plant stems. Leafhoppers are often brightly colored and frequently have their hind legs cocked and ready to leap away from would be predators, but not quick enough to leap away from this robber fly. While out in the field next time, take a closer look. 

Posted by Bill M. on 10/04/2017

   
Subscribe to Feeds
 
Categories
 
Authors
 
Archives
CONTACT US 719.683.7960 info@chicobasinranch.com