Monday, January 28, 2008

Central Texas Trail Tamers volunteer at BRP

The Central Texas Trail Tamers volunteer a day each winter to help the Bamberger Ranch Preserve. Their knowledge of trail development and maintenance is valuable to us, and they have done some wonderful projects here.

Below J. David and Lynda DeGroot stopped work and smiled for the camera as I walked along the Lindheimer Trail taking pictures of volunteers hard at work. Lynda has been with the Trail Tamers for many years and is the person that we count on to communicate with their members and make arrangements for their camp-out and work-day.

The Lindheimer trail, which is in Turkey Hollow, is several years old, but its remote location and abundance of Ash Juniper have kept it from being used often. Also, feral hogs have done a lot of damage by digging in the area, and so it was time for maintenance and clearing.

The morning activities were rock relocation, building steps in steep areas and removing excess juniper. Below are some volunteers that were concentrating on rock placement along the trail.

Below a chain saw is used to cut juniper into pieces that can be easily hauled to the tree chipper.

Stephanie, who is engaged to our new employee Justin Duke, helps pull brush down the hill to be chipped.

Justin loads juniper limbs into the tree chipper.

The chipper grinds up and delivers a stream of chopped material which will be used around the ranch on trails and in gardens.

Aiden, Steven and Amanda Fulton's 18 month old son enjoys walking on the new mulch bed in Colleen's Butterfly garden. The flowering plants and bushes in the garden are glorious during the warm months, and attact bees as well as butterflies, and provides food for caterpillars.

Big Steve and Aiden enjoy sitting on the porch and watching people exploring outside the Center.

I missed the afternoon activities, but it was wonderful meeting volunteers in the morning. Thank you all so much for the work you did!

If anyone took a group picture and would like to send it to me, along with names (if you wish), I would be delighted to add them to this post.

Sunday, January 20, 2008

More About Bats, and Selah Winter Bird Count

A Little More About Bats

Illustration by Margie Crisp which is part of a larger illustration used on a T-shirt.Note the "free-tail" that reaches beyond the membrane.

This illustration of a bat-wing shows the arm bones and finger bones and how, with a membrane stretched across them, they form a wing. (Adapted from Bats, by M. Brock Fenton).

Photograph by M Bamberger, cropped and manipulated to bring out details in the wings

Recently, researchers who went into the Chiroptorium informed us that the wooden boxes inside the cave were full of Mexican Free-tailed bats. We knew there were bats in them, but assumed that they were Cave Myotis, another species of bats that share caves with Mexican Free-tailed bats, that frequently stay in Texas during the cold months. This is very interesting, and we are wondering if the bats have a source of food. Dr. Kunz told us he would like to come back soon and try to find out what, if anything the bats are eating. I'll include such information in a future blog when and if we find out.

The image above is a close-ups of part of an image that was in the most recent blog of January 11. Chris Johnson suggested that there might be information in the digital image that could be brought out with manipulation. So I tried, and now you can actually see bones of their fingers- which are the reason that bats belong to the order Chiroptera which means "hand-wing". Their fingers hold and shape their wing membranes, most clearly in the bat at the upper right of the picture. I am surprised by this, and excited because it was late afternoon when I took it, the light was poor, and they were flying by very rapidly. You can also see a little tail extending past the membrane between their feet, which explains Free-tailed as part of their name. Many species of bats don't have any portion of their tail extending beyond their feet.

Winter Bird Count Spots a Total of 42 Species

We held our Winter Bird Count today, which is one of three counts we hold each year and have been doing so for 7 years now. The weather is usually cold in January and we frequently get low numbers of species, especially when we have a stiff wind and/or rain. This year it was cold and windy, but clear.

The volunteer birders are led by Marsha May who is an excellent and avid birder. She is president of Travis Audubon Society, which is a big job and I have heard that she is doing an excellent job. Marsha is the person who communicates with our volunteers to let them know when bird counts are scheduled. We invite those that are interested to arrive the night before, bring a dish and join in the "pot luck" dinner, followed by a night hike, a slide show, or just sitting around the fire chatting. Bunks are available for our overnight guests in the dormitory wings of The Center.

The adventure starts at dawn, and the groups are out on their area when the sun comes up. Each group has a person who knows the ranch roads, a very good birder that knows birds by sound as well as sight, and one or two people interested in learning more about birds. We drive to interesting areas, and frequently walk to good sites. We bird until noon, when we return to The Center.

The "count-down" determines the total number of species seen and if a new species to the ranch was observed. A representative of each group indicates whether or not a bird was seen when Marsha reads the list out loud. We had five groups out on Sunday, which cover a large portion of the 5500 acres of the ranch. We look for birds in broad valleys, along creeks, lakes and tanks (Texas speak for ponds), open fields, canyons, brushy hillsides, and the flat remnants of the Edwards Plateau which are our "hill tops". Thus most of the different habitats are checked. Without exception, no one group sees all the birds that are identified during a bird count.

Below is a photograph of most of the participants, and including the two that didn't go with a group. (Margaret and J. David showed up for the count-down).

Birders for Winter Count, January 20, 2008

J. David Bamberger and our new employee in Education at BRP, Justin Duke.

Marsha May conducts the Count Down for the day.

Birds seen on 1/20/08 that had been seen on other Winter Bird Counts:
Wild Turkey, Black Vulture, Turkey Vulture, Red-tailed Hawk, American Kestrel, American Coot, Killdeer, Mourning Dove, Golden-fronted Woodpecker, Ladder-backed Sapsucker, Eastern Phoebe, Western Scrub-Jay, Common Raven, Carolina Chickadee, Black-crested Titmouse, Carolina Wren, Bewick's Wren, Ruby-crowned Kinglet, Eastern Bluebird, American Robin, Northern Mockingbird, Orange-crowned Warbler, Spotted Towhee, Rufous-crowned Sparrow, Chipping Sparrow, Field Sparrow, Lincoln's Sparrow, White-crowned Sparrow, Northern Cardinal, Meadowlark, House Finch, Pine Siskin, American Goldfinch

Birds seen that had not been seen on previous winter counts: Crested Caracara, American Woodcock, Pryrrhyloxia

New bird for Selah: LeConte's Sparrow

Photographs taken by Margaret Bamberger on 1/20/08.

Friday, January 11, 2008

Crazy About Bats!

Bats, the Chiroptorium, and bat researchers.

The Chiroptorium is our man-made bat cave. Chiroptera is the order for bats in the family of Mammals, which is the origin for the first part of the name Chiroptorium. The second part of the name "torium" comes from the end of auditorium which is a large place for a gathering. So, Chiroptorium is a large place for bats to gather. In March each spring, Mexican Free-tailed Bats (Tadarida brasiliensis) arrive in large numbers from their winter homes in Mexico, Central and South America. Because our cave is a nursery colony, most of the bats are pregnant females. They leave each evening as the sun sets to find food, which is lots of flying insects, especially moths.

In the middle of June one baby is born to each mother bat. The babies, naked, pink and flightless, are deposited in a contiguous area on the ceiling or wall of their cave. The heat generated by all the close bat-bodies (up to 400 per square foot) help to keep them warm. Mothers leave their babies in the cave when out hunting for food at night. Each mom relocates her baby by calling to her pup when she returns. As she gets close she can also smell her offspring. Her milk is rich and high in fat, and her baby grows quickly, and within a month the pups are nearly as big as an adult, furred and ready to fly and feed on their own.

Dr. Gary McCracken on the left in the above photo, has done a lot of research in Texas, which has increased our understanding about Mexican Free-tailed bats, how they live, what they eat, and how important they are to agriculture. Using weather balloons with echolocation sensors on them, he was able to find out that free-tailed bats find and fly into clouds of migrating moths that they love to eat, and which provide them with important nutrition. These moths lay their eggs on corn, cotton and other crops, and the caterpillars eat the developing plants. Therefore having bats eat lots of moths before they have a chance to lay their eggs is beneficial to farmers.

The huge colonies of Mexican Free-tailed bats in Central Texas live mostly in caves, but are also found under bridges like the Congress Avenue Bridge in Austin, and in culverts. When an continuous stream of bats emerge in the evenings for many minutes, and even hours, it is hard to imagine how many bats are flying in front of you. Until the last few years there was no way to accurately count the numbers, until Dr. Tom Kunz, from Boston University, on the right in the picture above, developed a method using infrared video photography and computers. A continual infrared image of the bats emerging from the mouth of a cave, in which the warm bodies of the bats appear like little white dots moving against a dark background is read by a computer and the total number calculated.

One of Dr. Kunz's post-doctoral students, Dr. Nickolay Hristov, shown with his new Belgium sheep-dog three month old puppy, Coda, and another graduate student, seen below, Louise Allen came to The Bamberger Ranch in 2004 and conducted a count. The next spring they started a regular once a month count of our bats during the time the bats are in Texas. I remember the early counts were below 10,000 bats. However, we were thrilled when we realized that there were babies in the cave, which meant that even though the numbers were small, we had a nursery colony. Each year since then the numbers have increased dramatically and this year after the babies were flying the number reached 121,000.

Louise Allen-Hristova, who is now married to Nick, had also been researching the effects of stress on the growth of young bats. She has finished collecting information for her dissertation, and is now writing it. She will be awarded her Ph.D. soon.

Another doctoral graduate students of Dr. Kunz that has worked on our counts is Jon Reichard, seen above with his wife Jen who is an 8th grade science teacher. That's J. David Bamberger smiling on the right.

The research by Dr. Kunz's team has included counts on many of the Central Texas caves as well as Carlsbad Cave in New Mexico. This has added an important chapter to our knowledge of bats. We certainly thank them for their work here at Bamberger Ranch Preserve, and for their friendship.

Bat Conservation International (BCI), whose headquarters are in Austin, has a great deal of information about bats in Texas that is available to the public, both on line and in books that are for sale from their bookstore, which is also on line. In the months when there are nightly emergences from the Congress Avenue Bridge over Lady Bird Lake, there are specialists from BCI there to tell you about the lives of bats and how important they are to humans. It is a wonderful show, and I recommend that you get out and see it.

Monday, January 7, 2008

My Son and Grandsons Visit Selah

On a very nice day in late December (after Christmas), my son Chris brought his two boys out for an afternoon at the ranch. When I showed them my most recent post about Charlene and her children visiting the dinosaur tracks and fossil hill, they told me that they really wanted to be on my blog too. We decided to take a trail walk along Miller Creek, and they would try to find interesting things for me to write about. So off we walked and I had my camera. Because they are much closer to the ground and have such good eyesight, they notice much more than I do, and find lots of things for us to examine.

Gabriel sits on the dam at Jacob's Ladder, which is the name of the area and the tank.

Eli shows how slow the water is going over the dam now because we haven't had much rain recently.

Chris, Eli, and Gabriel on the Louis Bromfield Trail which runs along Miller Creek. We started at Jacobs Ladder tank and we were traveling upstream, and the end of the trail for us was across from Hes' Country Store.

Gabriel gets a hug from his dad.

Eli is showing me a tiny frog that he caught on the creek edge.

When Eli tossed the Blanchard's Cricket Frog (Acris cretipans blanchardi) into the creek it swam back to the shore, and I got this nice picture of it next to a Spanish oak leaf that shows how very small it is! According to my guide book, Reptiles and Amphibians of Texas by Garrett and Barker, this little frog is from 5/8" to 1.5" long and its call is a succession of clicks that sound like river rocks being tapped together. It is a common frog that is found in much of Texas, except the far eastern and far western parts of the state. In the warm months, when you walk up to a pond, if you tap rocks together Cricket frogs will frequently answer you. Start your clicking slowly (about once per second, and then gradually increase your speed. Stop after about 5 seconds and listen to hear if you get a response.

Eli found this rock that has a mostly smooth rounded indentation and a few parallel lines that start in the shadow and run about a third of the way across. It could be a fossil, but I don't know what kind it might be.

Gabriel likes to throw rocks into the creek.

The dam across the creek near the snowbell section of the Bromfield Trail has stepping stones so you can cross it easily without getting your feet wet.

Only a small amount of water was flowing a week ago.

During this past summer when we were getting a lot of rain, the amount of water flowing across the dam was considerably greater.

In the winter when the grasses are shades of grey, brown or rust, if you see a plant that looks like a large green grass plant it is probably Nolina lindheimeriana or Sacahuista, also called Beargrass which is in the Agave Family. Its leaves are long, thin and very tough, and Native Americans used them for weaving baskets.

Imagine my surprise when we saw this Bagworm bag, which was on a small Plateau Live Oak near the creek. The bag is made of liveoak leaves which are woven into a silken bag which covers the body of a caterpillar, or larval stage, of the Bagworm moth. The adult male has a dark fuzzy body and clear wings. The adult female doesn't have wings and stays in her bag. A male finds her and after they mate, she produce lots of eggs which stay to hatch in her bag. When the eggs hatch tiny caterpillars lower themselves on threads, find food, and make a tiny bag that they carry around with them. Eventually when they are larger each one makes their own hanging bag and the cycle is repeated.

This egg-case which is a little less than one inch long was made by a female Praying Mantid. It was on a Kidneywood bush and it was easy to see when the leaves were down. There were 100's of eggs in this case and it looks like they hatched out months ago. When I was sitting at a picnic table at Madrone Lake one spring, I noticed hundreds of tiny praying mantids crawling on the top of the table. I looked underneath and could see the eggcase was attached to the picnic table leg. Because Praying Mantids eat insects that eat plants, I was happy to see them.

Spiders like this one are often seen running around during the day. (Animals that are active during the day are diurnal, and the ones that are active at night are nocturnal). It is probably one of a group of spiders known as Wolf Spiders that have good eyesight and hunt for prey insects on foot, or wait for an insect to walk close so they can ambush it.

In this close-up you can see the spider's 2 large front eyes, which allow them to see well. All spiders have a total of 8 eyes, but in wolf spiders 6 of them are very small.

Note: Photographs were taken by Margaret Bamberger on a Conon XTi digital single-lens-reflex camera on the 29th of December, 2007.

Tuesday, January 1, 2008

Outdoors during the holidays

Schedules tend to be open during the holidays, and friends who are usually at work or school can visit. During the nice weather we'd had recently we've had visitors that have enjoyed the scenery and activities here.

On December 22nd a group of us celebrated the winter solstice, which is the shortest day of the year.

We walked along the Lindheimer trail that is named for a famous early Texas botanist.

Here a we sit within a circle of Lacey oaks.

Laurie, a friend of mine, came out Saturday (December 29) with her daughter Carlene and her 3 children, Caitlyn 13, Peter 12, and Cameron 7. We started our adventure at the dinosaur tracks.

Comparisons of human foot size with the track size shows that the dinosaurs that made them were much larger than humans. Acrocanthosaurus, a meat eater that lived approximately 100 million years ago when our area was a sea shore, was about 25 to 30 feet from snout to tail tip. It probably weighed 2 to 4 tons, and had a mouthful of serrated teeth. It looked somewhat like T-rex but was considerably smaller and had longer arms for its size.

Next stop was fossil hill where many different kinds of fossils can be found.

The most common fossils are oysters, and they are the dominant fossil in this bed. There are other types of shells from critters in the same group, the Pelecypods (which include clams). A few snails, or Gastropods, and an occasional urchin, or Echinoid, are also found.

Commonly oyster shell fossils are found opened and the top and bottom shells are completely separated. Every once in a while an oyster is found with the top and bottom sealed together like this one in Caitlyn's hand.

Here is one where the two halves of the oyster were found together but when picked out of the clay bed they came apart. There is clay in the middle.

The limestone that was used to pave our road has lots of fossils in it and Caitlyn, Carlene, Peter and Cammy look for specimens as they return to our vehicle.

We visited fields where the Scimitar-horned oryx live. This type of oryx, which can no longer be found wild in its homeland, lived along the southern edge of the Sahara desert where grasslands existed. The region no longer supports grass due to drought and human development. They are part of the Species Survival Program and doing very well at Selah.

We stopped at Hes' Country Store on the way home, and Cammy decided that her stuffed penguin needed to have his picture taken with her and the wooden Indian on the porch.