Exclosure

Exclosure – (ex-clo’-sure) n. – an area protected by various devices against the entrance of animals and insect pests – from Webster’s New Universal Unabridged Dictionary.

Photograph taken by Lew Hunnicutt.

In February of 2000 Dr. Lew Hunnicutt, who was then in charge of Stewardship, Education and Research for us, set into motion on Selah a research project quite ambitious for a small staff and operation such as Bamberger Ranch Preserve. The project in Lew’s own words was to “Monitor Range Condition and Trend.” It was long range, a minimum of 5 years but our expectations were 10, maybe even 20 years! In 2001 and 2002 Lew, assisted by Margaret Bamberger and a very capable volunteer, Patrick Garnett, monitored and photographed the existing exclosures. As a result of their efforts, a very good baseline set of records exist. Unfortunately, in 2003 Dr. Lew left us to return to his roots, college level teaching. The regular monitoring required of the project soon escaped our attention.

I have admonished everyone here over and over, “Never initiate an action that you are unable to sustain,” whether it is a business, a marriage, a trail or a research project. Without Lew Hunnicutt, we did not have the time or knowledge to sustain the project; although Margaret led newly hired Ranch Biologist, Steven Fulton, to the exclosures and together they recorded observations and took photographs. However before the next scheduled visits, Margaret was diagnosed with cancer and her involvement was no longer possible.

Before moving to 2009, let me describe for you just what and how and for what purpose the exclosures were installed. Once again, in Dr. Lew’s own words excerpted from his plan:

“The condition of rangeland (i.e. excellent, good, fair, or poor) is a direct result of the management practices imposed on it. Determining condition alone is not enough; we must also monitor the direction of change in condition over time (rangeland trend). Trend can be upward (positive), stable (positive or negative), or downward (negative). This dictates to us whether or not our animal management program is beneficial or detrimental to a particular range, site, pasture, etc. If detrimental (downward trend), changes can be implemented to move a site back toward an upward trend.

In order to monitor condition and trend on the ranch, 13 exclosures (more to be added in the future) were constructed in February of 2000. Each exclosure was constructed using 2, 20-foot cattle panels pulled into a circle with the overlapping ends wired together. Each exclosure was then wired to 3 t-posts driven into the ground for support. The 13 exclosures were divided among 5 different range sites (a classification of land based on soil type and properties) across the ranch in areas determined to be important from an animal use standpoint. The purpose of each exclosure is to keep out large ungulates (cattle, deer, and goats), while still allowing use by small animals (rabbits, quail, etc.). Baseline date (i.e. species composition, extent of cover versus bare ground, height of vegetation, etc.) was documented at each exclosure. A permanent photo point was also placed at each exclosure site. This photo point was simply another t-post driven into the ground in close proximity to the exclosure. To collect photo point data, a camera is placed on the top of the post with the lens pointed in the direction of the “tail-of-the-t” of the t-post. The picture is taken then the camera is turned 180 degrees to capture a photo in the opposite direction. This insures that the same areas will be photographed during each data collection period. The purpose of photo points is to look at changes in the land over time. Photos can be compared with previous years to determine the trend (upward, downward, stable) of the site. The key to using photo points is to not get in a hurry. It is impossible to draw conclusions after only a few years. It takes a minimum of 5 years and it is even better with more years worth of photo data before conclusions are drawn about the trend.

We will visit each exclosure at least twice (more as needed) during the year to document species composition, forage quantity inside and outside each exclosure, and to take photo point photos. The visits will occur during the growing (May/June) and dormant (Jan/Feb) seasons for many of the plant species found on the ranch that are of major importance to large ungulates. This data will allow us to monitor condition and trend over time. This is a long term study, basically never-ending, project.”

Over the past 5 years while rounding up cattle or guiding a hunter, Scott Grote, Ranch Operations Manager, made a few casual observations of the exclosures. Nothing was recorded.

Now fast forward through 2004-2005-2006-2007 and 2008. In late August 2009 Steven Fulton, Ranch Biologist, with me and my dog, Cory, tagging along visited, inventoried and photographed all exclosures.

Like tree rings divulge age and weather, the exclosures, along with our weather and livestock records give us valuable information.

Photograph taken by J. David in June of 2009.

See what may occur if rangeland is not managed. Grazing cattle or browsing deer are management tools. Inside the exclosure, woody species have essentially taken over. The tall plant is a Hackberry tree which will eventually provide bird food. Primary vegetation is Greenbriar, a preferred plant for deer, but currently over represented throughout the ranch. There is also a very large spreading Agarita which I would describe as somewhat invasive. There were 3 forbs: Orange Zexmania, Vetch Sp, and Shepherds Purse; some Texas Wintergrass; and K.R. Bluestem, but overall the cover inside was 65% woody with 156” height; while outside the exclosure under managed (grazed) conditions, the cover was grass.

Photograph taken by J. David.

Here on this adobe site there is not much difference inside or outside our exclosure. The ground cover is 45% inside and out of the exclousre with grass cover 6 to 8 inches inside. The grasses are primarily Seep Muhly, Little Bluestem and Tall Dropseed. Steven indentified two forbs, Queen’s Delight and Navaho Tea, and a succulent, Twisted Leaf Yucca, which hadn’t been recorded in those first three years.

Photograph taken by J. David.

Grass cover was estimated at 95% and 10 to 12 inches tall within this exclosure with K.R. Bluestem being most abundant followed by Little Bluestem, Silver Bluestem, Side Oats Grama and some Tall Dropseed. One forb, Vetch Sp, was noted as well as Greenbriar, a woody. It appeared that grass production was beginning to mulch itself.

Photograph taken by J. David.

This is on our Redlands Range site. A small, perhaps a 50 acre area in which Post and Blackjack Oak dominate. There are very few other oaks in this area. 85% cover, 6 to 8 inches high and mostly grass was identified within the exclosure. They being K.R. Bluestem, Little Bluestem and smaller amount of Sideoats and Indiangrass. There were no identifiable forbs, outside the exclosure grazing and hoof action had hampered our ability to identify anything. We noted that in 2003 this location held a nice diversity of grasses and forbs. Please read on through the next exclosure for comments about this as well as other thoughts on our exclosure project.


Photograph taken by J. David.

I was unable to identify which exclosure this was so I passed the question to Steven Fulton, our Ranch Biologist, with the comment, “Tell me about this one.” The following is Steven’s written reply:

“My first impression of this pasture as I approached this exclosure was that it is overgrazed. However, when our 30 inch deficit in rainfall of the past two years is thrown into the equation the condition of this pasture begins to make more sense. The physiological response of many of our native plants is to retreat into a state of dormancy when faced with severe drought. Our seemingly dead grass is only dead above ground; the life of the plant persists in the roots. Cattle removing dead grass blades and stems should not change the species composition of this grass community. Inside the exclosure, the dominant species is Little Bluestem. To determine the degree of overgrazing (if any) in this pasture, a return visit after a wet period is warranted. I expect to see the pasture composed mostly of Little Bluestem, meaning that overgrazing has not occurred. However, if the grass community shifts to less desirable species (threeawns) then overgrazing has occurred. Let’s pray for a wet fall and spring so I can answer this question about overgrazing.”

I’m not pleased with this, my first report on the exclosures. However I am enthusiastic about the project. It was very interesting to see the changes at each site and to look at Lew Hunnicutt and his volunteers’ comments and inventory of the plants. Now that we are back and involved with this research, I expect to be much more thorough when monitoring and collecting data. . . . . What can we say about all of this at this time?

• Well, we could tell which sites cattle preferred.


• It was wrong to conclude any site was overgrazed due to poor management since we had two serious drought years with no water in 4 pastures. So, in spite of reducing our cattle herd by 60%, cattle had to be grazed in pastures that had water.


• There was a lot of dormant grass that has begun to green up since recent rains.


• Rangeland unmanaged will result in woody species that begin taking over.


• As a precursor to climate change, we may learn which plants can adapt.


• It would be more valuable if we had checked our project in a more normal climate year, but what really is normal?

As Lew Hunnicutt said – “the project has more value if extended 20 years,” and it’s our goal to do just that.

Research That Follows Work

The beginning of our work to rescue the federally and state listed endangered plant, Styrax platinifolius ssp. Texanus, commonly known as the Texas snowbell, was in 1994. This beautiful plant is a small tree or shrub native to the watersheds of the Nueces and Devils River of west Texas.

I spent the first five years following leads from other botanists, looking in various herbariums and going door to door (ranch to ranch) in Real, Edwards, Uvalde, Kinney and Val Verde counties. Eventually, we secured landowners interest and support to save the plant from extinction. My message was that we private landowners could demonstrate our commitment and stewardship without the government’s regulation. A number of landowners agreed. Their combined ownership exceeded 100,000 acres. During this time, we collected small quantities of seed and began propagating and growing operations here on the ranch. In 2003 we began the recovery project by introducing the first of what would become 682 plants.

All introductions, under agreement with the U.S. Fish and Wildlife Service and The Texas Parks and Wildlife Department, are planted in the watershed from where the seed was collected. Plants are all corralled (caged) with five foot high 4 x 2 horse fencing supported by six steel t-posts. Each corral is six foot wide and contains three snowbell plants. We believe these will protect the plant from herbivory for 75 years and allow room for regeneration within the structure. Doing all the very hard labor of carrying materials, water and plants into steep canyons, over rocks and through thick brush would not have been possible without the help of many volunteers. Now the project has reached a point that scientists desire more knowledge and information about the plant. Steven Fulton, our ranch biologist, has chosen to answer scientists’ questions as part of his thesis for his graduate degree at Texas State University in San Marcos. The following describes the questions that Steven’s research is designed to answer:

Review of the Recovery Plan has illuminated many questions concerning the ecology of the Texas snowbell. Some believe that the Texas snowbell is confined to such inaccessible places as cliff faces to escape herbivory; however, there is only anecdotal evidence of animals consuming Texas snowbells. Evidence gathered through observation will prove or disprove that herbivory is a threat. Others believe that the Texas snowbell grows in such places because the presence of surface water creates a microhabitat with lower temperatures and higher relative humidity; however, no site specific climatic data is available. It is presumed that Texas snowbells reproduce via outbreeding and insect-pollination; however, these assumptions have not been verified and the pollinators have not been identified. As a result of their position above or near water, many of the mature seeds drop into water. The effect submersion has on seed viability is unknown.

To aid in the management of this species there is a need to identify its pollinators, to record its microclimate characteristics, and to determine if there is a correlation between seed submersion and viability. Information obtained from Steven’s research will improve the survival rate of reintroduced plants as well as provide information and understanding concerning the ecology of the Texas snowbell.

The snowbell blooms for approximately two weeks in mid April.

A distinguishing characteristic of the Texas snowbell is the white pubescence on the underside of the leaf. This is the only apparent difference from its close cousin, the sycamore leaf snowbell which we have growing naturally here on the ranch.

Looks can be deceiving! Between Steven and the mountain in the background flows the beautiful, crystal clear Devils River. This is in Val Verde County on the Nature Conservancy’s Dolan Falls Preserve. Here Steven is unpacking some of the scientific equipment he uses to collect data.

Here are the scientific instruments Steven has installed to collect data. The instrument in the foreground collects temperature and humidity and the one in the background records rainfall. These are delicate battery powered instruments.

Steven’s 6’8” height comes in handy when mounting a motion detecting camera which will produce a photograph of any animal that might come by and choose to browse the snowbells. Early results show Aoudad sheep browsing.

All of the research is not accomplished with scientific instruments! Here Steven has shrouded branches on the plant prior to its blossoming. Notice the flowers on the unshrouded branches. Steven will remove the shrouds and sit for hours observing what insect pollinates the snowbell plant. Up until now, this is totally unknown. Because this is scientific research, it is premature to make a statement about the pollinator until the work is complete.

Another shrouded plant overhanging the Devils River.

Here Steven retrieves information from the instruments into his laptop. This set up is on the Nueces River.

Steven must visit all of his installations once a month. Sometimes it takes two or three days to travel out to replace the batteries and extract the information. He spent ten days at the beginning of his research installing the equipment.

This was a gamble! On the cliff which was inaccessible to us from the top or from below, we had discovered some very healthy plants. In an effort to collect seed we drilled into the cliff and placed ten foot rebars to support some galvanized screen. To our delight we caught over 100 seeds in our net and from these seeds we have grown some healthy plants.

Steven has another year before he will be publishing his research and defending it at the university. We will bring the results to you at that time, but feel free to communicate with us if you have further interest.

Bluebirds Set up Housekeeping at Selah

Bluebird images captured by Amanda Fulton

Amanda with Steven and Aiden last summer at Madrone Lake.

Amanda teaches biology at Blanco High School. She is married to Steven who is a biologist and teacher here at the Bamberger Ranch Preserve. They have a son, Aiden who was born on the 4th of July in 2006.

This past weekend, Amanda set up her camera in the yard in front of a bluebird box that a pair of bluebirds had chosen as their nest box. For hours she sat, watching and taking pictures. The six bluebird pictures in this blog show both the characteristics of the male and female, and the care the male gives the female during the nesting period.

I have asked Bamberger Ranch staff members for contributions such as pictures and ideas for the blog, and am thrilled that Amanda took these pictures.

Bluebirds are one of the Thrushes (a sub-family of birds). Thrushes have thin bills, strong legs, and many have beautiful songs. Both insects and berries are important to their diet.

Eastern Bluebirds (Sialia sialis) are in Eastern and Central United States including Texas. There are also Western Bluebirds which are seen in far West Texas. Flocks of Mountain Bluebirds are seen here sometimes in the winter.

They are a medium sized songbird, 6 to 8 inches from head to tail. They have a wingspan of 10 to 13 inches. They weigh around 1 ounce.

As is true with many bird species, the male is more brightly colored than the female. The blue on this male is a uniform and intense color , and the chestnut marking of his chin and breast is a rich color. His belly is white.

In this picture of the male bluebird you can see what a lovely blue is on his back - from his head to his tail.

This female bluebird's picture shows her grey-blue face, white eye ring, and the soft chestnut color on her breast.

The female is sitting in the opening of her nest box as she waits and watches for her mate to come back, hopefully with a delicious insect or berry.

Her mate has returned with something for her to eat, and she eagerly accepts it.

Now that she has eaten he gets ready to fly away, perhaps to find something to eat for himself or perhaps he'll find more food for his mate so that she can produce healthy eggs.

Before people started putting out bluebird nest boxes, bluebirds were having a hard time finding appropriate nesting sites that weren't taken by other birds, such as European Starlings and House Sparrows. People that liked seeing and hearing bluebirds decided to make nest boxes especially for them, and now the numbers of bluebirds have increased dramatically. We have put up lots of them here.

Many Audubon Society groups have developed "Bluebird Trails" in parks and on private land. Members put up lots of nest boxes, and and develop trails with good spots for watching bluebirds come and go with food for their nestlings.

Typically the female lays 4 or 5 pale blue unmarked eggs. Incubation lasts for 13 to 16 days. Both parents bring food to for the nestlings. Young birds leave the nest at around 18 or 19 days. I have seen the adults feed them for a while after they are out of the nest.

Eastern Bluebirds typically have more than one successful brood each year. The grown birds from the first clutch will often help feed the latest youngsters.

Thanks to Amanda for these wonderful pictures of Bluebirds.

The Cornell Lab of Ornithology has a wonderful website with lots of interesting visual things including a Nest Box Cam of bluebirds, which should start their 2008 season soon (within the next week or so). Last year the cams started being shown on the website in March. Some of the nests were successful and some were not. Some of the pictures from the cams during the spring last year (2007) can be viewed now.

Try to get out and enjoy the birds this spring. There is a lot of activity now, and nesting sites are being chosen and nest building is starting. I'd love to hear about things that you find! If you send answers in the "comment" section I can publish them and everyone can read them! You can use your real name or make up one. If you don't want your comment published let me know.

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.