Bearing up to migration

Birders witnessed a bear bathing in the stucco tank. First time anyone has seen that. Previously, the bears bathed in the big, now destroyed, tank. The birders were sitting in the viewing blind when they heard loud splashing in the nearby tank. A poor photo was snapped of the culprit as it fled the scene.

I spent three intense days at the oasis and didn't want to leave. Good birds and fun birders! Here's the Vent group from the 25th. I'm a couple days late in posting it. Had meant to post it in last blog post, but was really exhausted. I plan to go back in a couple of days. Spring migrations only happen for two weeks every year and I want to enjoy them as much, and for as many years, as possible.

The back water drip is a magnet to birds.

Green-tailed Towhee

Newly hatched Black-chinned Hummingbird

Tomorrow I plan to inventory the birds here at our ponds in Alpine. One of the mulberry trees has some ripening berries, enough to keep it busy with birds anyway. 

Western Tanager

I was given an award at the recent TOS Spring meeting. Here's a quote (by Crystal Ledezma) about it. 

"I am particularly excited about our new award, the Dennis Shepler Birding Ambassador Award, given to Carolyn Ohl for her generosity in sharing her oasis with us. I had the honor of going with Ron to film an interview with her. His finished video was amazing, I cried thru the whole thing. The Christmas Mountains Oasis is a special place, and Carolyn is a very special human, it was a great honor to be involved in this."

I'll get a link to the interview and post it here soon.

Big migration day

A relaxing lunch after an morning of intense birding.

Today the oasis hosted the annual Victor Emanuel Nature Tours (VENT) group. As always, a fun group. We saw plenty of birds to keep everyone on their toes. This leucistic White-crowned Sparrow was quite entertaining.

And great to see a Lark Bunting in full breeding plumage.

An Indigo Bunting seems to be surveying the wreckage of the big tank. Actually, he's probably looking for a safe spot to drink and bathe on his journey north, and couldn't care less about the tank.

The Common Yellowthroat seems to have had his fill of shrimp, and looking to vary his diet.

I focused on helping the visiting parties today with their quests and questions, so didn't pursue taking many photos.I think some visitors got pictures of this lovely male MacGillivray's Warbler, but I only got this poor trail cam shot. 

And I'm exhausted, birding from dawn until after dark. Not complaining. Hope to blog more about great birds in the next few days.

Migration excitement underway

Always a busy, crazy time! I went to the oasis yesterday and saw a lovely male Hermit Warbler, got the watering done, feeders serviced, then rushed to Fort Davis to see a Bobolink in birders' yard. I hadn't seen that species since I was a child in Iowa, like more than 60 years ago.

I had to drive my husband's big pickup to go to the oasis, and needed a stool to get into it, which was a big pain. After I got back to town, my pickup was ready, so I won't have to do that anymore, I hope.

Here's what a failed tank looks like nearly a month after a monsoon...

And here's what it would normally look like at this point after a monsoon...

Just gotta accept what I can't change.

Last night I went to check to see if the Elf Owls are nesting in the same hole as last year. They're nesting in the same agave stalk but a hole 3-4 feet higher up. I really need to get them some newer stalks. These are just about worn out.

Never a dull moment!

I'm totally ready for some dull moments. I went to the oasis yesterday afternoon, anticipating watching birds forage on Fairy Shrimp. My son was down there and had sent me numerous photos of a Common Yellowthroat and Northern Waterthrush gorging on the shrimp.

Not long after arriving, I was happily photographing the action as best as my poor abilities would allow. I got the yellowthroat and waterthrush gobbling up shrimp until I wore myself out.

I later learned that the waterthrush I photographed was a Louisiana Waterthrush and the one Lee had photographed was a Northern Waterthrush. Crazy! The Louisiana is more rare for here.

At daylight this morning, I was determined to give all the trees a good watering. The plan was to nap afterwards, and then go to Alpine. Staying awake driving to town mid-afternoon is very dangerous for me without a nap first. I was pleased with how smoothly everything went. My son went to town around midday, but I assured him I could carry on alone. I was glad I was able to take a short nap. Sometimes I'm unable to sleep when I have the trip to town ahead of me. All good.... until it wasn't. 

I got about five miles down the road when my pickup died. 100° outside. End of AC. Luckily, I was able to coast to the blacktop road, which was ever so slightly downhill. There, I got an unreliable bar of cell service and managed to call my son and husband. While I waited the two hours for my son to get there, a friendly neighbor shared his AC vehicle with me. I felt horribly guilty for all the work I cause my son. Seems like my care is a full-time job for him. They're talking like I need to get realistic and not go to the oasis so much. I think I just need a newer 4X4 vehicle, but either way, I'm continuing to go maintain feeders, and at least help with watering.

My pickup is an old 2011 Ford Ranger with over 200,000 mile on it. A couple of months ago the fuel gauge wasn't working, so the garage put in a new fuel pump. To do that they had to remove the gas tank. All seemed to work fine until a week ago when I filled up the tank after returning to town from the oasis. It only held half as much as usual. Weird! Then I started smelling gas all the time. Weird! And the breakdown today was the result. Somehow, I think something went wrong involving the gas tank. We shall see!

Continuing challenges

Now that the broken tank has lost most of its water, the catastrophe is easier to see.

Thankfully, the stucco tank is leaking very little. Some years my patching holds good and some years it doesn't, so I'm grateful for that. As I was looking at it today I noticed it is jam-packed with mosquito larva. Never saw a tenth that many ever before. By tomorrow I'd say the oasis is going to be swarming with mosquitoes. At least it's temporary, but will put a definite damper on migration birding. On the bright side, birds and dragonflies will be happy! Hopefully, birding will be awesome (with enough protection and DEET)!

Here's a recent photo by Kim Morse that I like. Male Lucifers challenging one another over feeding territory.

UPDATE: Ben Schwartz, Biology Professor at TSU in San Marcos TX, and Director of Edwards Aquifer Research, informed me that those are Fairy Shrimp, and not mosquito larvae. I'm ecstatic! Thank you, Ben! Never had a March monsoon before, so new territory for me! I thought it was strange to have mosquito larvae in such deep water! My son went and took a better photo:

New oasis reality

This will be an analytical accounting of the big oasis tank; its creation, loss, and what went wrong. I'm writing this as a record, the only one there is, hoping when I'm gone, it'll be documentation.

Back when my dear late husband, Sherwood, and I built it in 1997, we didn't think about how long it would last. If we had, we'd probably have figured something like 30 years. (It made it 28 years.)

Sherwood and me

We felt the tank would be too big to concrete, so we invested in a very expensive Permalon liner. As we put it down, with family's help, we left it plenty loose, plus the material was very stretchy. Once that was done, I went to work at beautifying the edges. For a month I hauled tons of rocks to anchor and beautify it.

It was exhilerating to watch it fill for the first time, and finally not lose all the precious flash flood runoff. I estimate it holds between 200,000-250,000 gallons.

I wasn't prepared for the problems ahead. First, the weight of the water caused the ground below, and probably the walls even more so, to compact and recede, which wasn't a problem at the time, since the Permalon was stretchy. In this next photo, you can see how taut the sides are stretched with the weight of water. If the Permalon hadn't been stretchy, it would have pulled my rock work into the tank. Of course, in hindsight, I should have left at least a foot of slack in the tank on all sides. There was plenty of material to do so.

Next, deer and javelina got into the tank. Their hoofs poked holes in it. That by itself, couldn't be tolerated. But also, javelina couldn't get out the slippery sides, and drowned. So I patched the holes and fenced the tank. 

That didn't work. The fence didn't keep them out, and where it went across the spillway, so much debris accumulated that water couldn't enter the tank. The first surge of a flash flood carries tons of debris in it. Not to mention, a fence ruined the ambience.

The only other option was concrete. We knew we couldn't do it alone, so we hired a crew. They were all set up inside the tank when we discovered that, while the concrete they were pouring was sufficient  weight on the liner floor, it wasn't heavy enough to make the liner lay againt the sloped sides. I'm sure the more it stretched, the harder it would be to stretch it further.

Two options, either remove all the rock anchoring/beautification, loosening the liner that way, or cut the liner.  It was May, with rain showers happening almost daily. The floor was already mostly done. We didn't know how long it would take to finish the project, but more importantly, when a monsoon would come. We couldn't chance leaving it vulnerable to a monsoon.  It took a month to finish the project and almost every night we removed the equipment, just in case. I felt I had no choice but to cut the liner.

Through the years wave action eroded the upper several feet of concrete wall. During construction, I had packed the cement onto a wire framework to hold it as best I could, but it was nearly 10 feet tall and too sloped for a ladder to stay in place, so not the best workmanship. Subsequently, I patched endlessly. One time, the late Bill Lindeman and Jane Crone came and helped with the patching. And it never held. Wave action would soon have it crumbling into the tank.

Bill and me in June 2011

Eventually the upper sides eroded beyond repair. Herds of deer and javelina were constantly clamoring up and down the sides, which hurt too. Here is the spillway area mid-December last year.

So now, the unthinkable has happened. I theorize that water coming into the spillway surged under the liner somehow, causing the tank to float and collapse. It's basically a dirt tank now. I expect it to be dry within a month... unless we get another monsoon.

The only thing that could have made the wire-concreted mesh buckle upward like that is the whole tank being pushed up during the deluge. Huge slabs of concrete came loose and tumbled into the tank.

The next photo shows the spillway where the water surged in and shoved the tank wall, such as it was, into the tank in a twisted heap.

Maybe when the tank is empty, someone can figure out a solution, but I'm preparing myself with the expectation of not being able to maintain as many trees as in the past. Also I plan to be more vigilant at patching the smaller "stucco" tank. With that not leaking, plus the new above-ground tank, the oasis might be able to survive almost as well, I think.  But a hard lesson re-learned..... nothing is forever!