Cave Gate questions

[Dan Straley]

I am in need of some opinions from other cavers.

In all my travels I have never seen a box style cave gate, except one place. One was built to cover a local cave near Brooksville, Florida. The design is to allow bats to freely roam in and out. The gate is 5 feet tall 6ft wide and 12ft long. It has thousands of pounds of hardened steel spaced 5 inches apart The gate resembles a mobile home and sits out in the woods exposed to the elements in the Withlacoochee State Forest. Another second box gate is being planned for a cave right next to it.

The builders of these gates are paid money to do so. Which to me is a way to support a lifestyle from impacting caves. I have an issue with this, but not as much as the gate itself.

Finally the questions,
Are you familiar with zinc strips for your shingle roof? Have you ever noticed that shingle roofs are always free of that blackstuff down slope from anything metal on the roof? That black stuff is plant life, and rain water passing over metals wash off oxidations that keep the plant life from growing on the roof shingles below.

Would iron oxide and whatever else that washes out of steel have this same effect on the life around the cave entrance?

We have a bat cave here in Florida that has an gate that is not very bat friendly, when compared to the "professional built box gate". Yet, thousands of bats fly through it everyday. Why? The gate is in a crevice about 2 feet by 2 feet and fissure shaped.

Bats are not using the box gate. I personally think there is a magnetic field issue due to all the metal, or scent issue, or obstructed view since the gate encompasses the entire cave entrance.

Thanks,

Dan

[Teresa]

Iron makes up 5% of the earth's crust, is the second most abundant metal, and the fourth most abundant substance after oxygen, silicon and aluminum.

Unless you have a problem with iron-fixing bacteria and algal bloom in the water, iron is not particularily toxic to most surface plants and animals. Someone else can answer the design problems.

[mgmills]

Cave gates are definitely a "sore spot" with many cavers

I am in need of some opinions from other cavers.

In all my travels I have never seen a box style cave gate, except one place. One was built to cover a local cave near Brooksville, Florida. The design is to allow bats to freely roam in and out. The gate is 5 feet tall 6ft wide and 12ft long. It has thousands of pounds of hardened steel spaced 5 inches apart The gate resembles a mobile home and sits out in the woods exposed to the elements in the Withlacoochee State Forest. Another second box gate is being planned for a cave right next to it.

I'm no gating expert, but I have been reading about different types of bat gates recently. I'm having trouble visualizing what you are referring too - is it kind of like a fence around the entrance? Do you have pictures?

There are people who have spent a lot of time studying bat behaviors and how they react to different types of gates. Do you know who designed the gate? What is their previous gating experience?

We have a bat cave here in Florida that has an gate that is not very bat friendly, when compared to the "professional built box gate". Yet, thousands of bats fly through it everyday. Why? The gate is in a crevice about 2 feet by 2 feet and fissure shaped.

Bats are not using the box gate. I personally think there is a magnetic field issue due to all the metal, or scent issue, or obstructed view since the gate encompasses the entire cave entrance.

Do you have information about the bat population before and after the gating? Who contracted to have the cave gated? The Forest Service? Have you talked to them about your concerns?

I'm not saying you are right or wrong but I'm not sure you have given enough information for people not familiar with the particular cave to have an opinion.

[NZcaver]

I'm no expert, but I doubt bat gates emit any significant magnetic field - not enough to result in a negative effect on bats, anyway.

This link shows a box bat gate I think is similar to the one you're describing. It was constructed several years ago on top of a mine shaft now being used as a bat hibernaculum. Cavers occasionally visit the mine to do bat studies, mapping, cleanups, etc, and as far as I'm aware the bats enter and exit through this box gate quite happily. It was installed by this company, who I have assisted (as a volunteer) on a more recent project.

I'm not sure I subscribe to your thinking of professional bat gate makers as those who merely support their lifestyle by impacting caves. If you read the comments on this page, you'll find that at least some of those who install the gates are acutely aware of the impact they cause. Installing a gate impacts a cave, sure - but how much impact is necessary to protect the cave (and it's inhabitants) from potentially greater impact? One could argue this fine line of cave conservation vs destruction all day long.

[Dan Straley]

Hi all, and thanks for the replies.. I'm learning here..

Teresa, Even though Florida is organic limerock and subtropical? from what I know (nothing), the plants here have not seen metals, as it does not exist here naturally. I can't help but to think that the large amount of metal wouldn't pollute the limerock around the entrance.. Please remember that I am only thinking and have no education on this matter. I am very familiar with the roof scenario I explained before. This is what sparked my curiosity on the matter.

Martha, The forest is gating the cave, but our grotto is flipping the bill. The forest wants the box gate, but I personally want to know it's the right choice. This particular cave has no bats and never has.. until recently no one ever really caved in it.. A new passage was found, which has expanded the cave much further and exposed and aquifer connection. Bat's could use the cave I guess, but it's very tight for a long distance past the entrance.

NZ Caver, You are very helpful.. That gate in the pictures is identical, though the builders are different. It's very good to see that bats are using that gate. As far as pro cave gaters, well, I am OK if they cover their expenses, wear and tear, and lost wages at their regular job, but I just don't like the idea of cavers (non-scientific/non-pro conservationist/non-rescue) making a living off of caves. I was always taught to volunteer. Volunteering is done for a need and that helps to keep things under control. Just my view of it..

Well I am posting here to be educated on these gates. Our grotto needs to make a decision and I want it to be the right one. Our caving community is chock full of bright individuals and I knew this was the right place to ask questions. Thank You!

[NZcaver]

As far as pro cave gaters, well, I am OK if they cover their expenses, wear and tear, and lost wages at their regular job, but I just don't like the idea of cavers (non-scientific/non-pro conservationist/non-rescue) making a living off of caves. I was always taught to volunteer. Volunteering is done for a need and that helps to keep things under control. Just my view of it..

Interesting view. I agree volunteerism is a vital part of cave conservation, research, caver training, and other projects. I also know that cave gates can be a touchy subject, and are often not the best choice for protecting a particular cave.

I'm still a little puzzled at your comment about pro cave gaters covering their own expenses, wear and tear, "lost wages" etc. Are you saying you expect these professionals - who run a business - to do this for free? Noble, but not very practical. What about cavers who make a living as guides in tourist caves? Do you feel the same way about them making a living off caves?

One gating project I was involved with a few years ago for The Nature Conservancy was headed up by a professional bat gate contractor, and two of his seasonal workers. They lived on site (camping) for a week with a few of us volunteers, and certainly weren't chalking up extravagant expense accounts. The overall cost of the project (estimated at $38k) was covered by a grant of just $17k from US Fish and Wildlife, along with labor provided by TNC employees, state workers, and a bunch of us unpaid volunteers. And when not installing bat gates, this company does a range of other caving/bat related work - including bat counts for state agencies. I'm guessing there's not always enough experienced local agency people or volunteer cavers available to do this either.

I can understand you feeling skeptical about contractors, in light of recent local experiences. All I'm saying is that using a professional bat gate contractor - preferably in conjunction with volunteer labor - may not always be as bad as it seems. I assume that at the very least, all the peripheral stuff like the design, materials, permits, insurance, liability, etc should be more manageable when using a contractor. Just my 2 cents.

Good luck with your project.

[batrotter]

The gate resembles a mobile home

I'd like to see a picture of that!

[J. Thomas]

We have a significant bat cave here in W. TX that has a gate similar to the one you are describing. It's not as "slick" looking as the one in nzcaver's link, but it works well. bats go through it, it locks, it keeps people out, it's certainly heavy enough for people to climb on it. It replaced one that was surface level and also meant to be bat friendly, but this one is better.

It was pretty much volunteer-built, and I think it was designed from plans provided by Bat Conservation International.

We have no naturally occuring iron and I've seen no evidence of the gate having an effect on vegitation below the entrance. But we also are don't get alot of rain (<19"/year).

With your roof flashing example, based on my commercial boating experience I think it's maybe the fact that the flashing is zinc-ed, not the iron, that's discouraging the growth. J.

[Komebeaux]

Plain and simple.



Gates aren't built to keep cavers out. They are built to keep those who mean harm to the cave and those who mean harm to it's inhabitants out.

In a perfect world, we could depend on people to do the right thing and not go into caves with spray paint, break formations, and disturb the bats. This is not a perfect world so we have to make an effort to protect these caves and biota.

If this interferes with someone's "sport" to the point of pissing them off, then they are not in it for the right reasons in the first place.

[J. Thomas]

I'm sorry, I wasn't clear about the keeping people out part. I didn't mean responsible cavers should be kept out. The cave I was talking about is on private property, on a very large ranch where it is pretty easy to sneak in, and the ranch owner who arranged for the gate didn't want anyone in his cave without him being there. Bats go in and out without the landowner's knowledge; people can't. J.

[Komebeaux]

I wasn't responding based on just your post, J. I was just making a statement on my view toward cave gates in general.

[Dan Straley]

Thanks again for the help.. We are faced with building a gate that will destroy this cave's natural entrance. Our grotto is being asked to pay for the gate, and well, we want it to be what is needed, nothing more, nothing less.

The box gate scared me.. NZ Caver should me that bats will use that gate.. that brings some relief.. My only other concerns are the destruction of the entrance and any damage the metals could cause to plant life.

To reply to NZ Caver, well I'm really bad at writing out my ideas.. Great in Math, bad in English!! What I was saying was, I'm OK with pro cave gater's paying for their expenses, but I want them to keep their day job.. Not to rely on cave gating as a source of income. It borders a conflict of interest in my book. I think that cave gates should be used out of need (whatever the need), and for no other reason. And if a pro cave gater sticks to those rules, then fine, but I might always be skeptical. Business is still business..

Thanks again..

Dan

[NZcaver]

Thanks again for the help.. We are faced with building a gate that will destroy this cave's natural entrance. Our grotto is being asked to pay for the gate, and well, we want it to be what is needed, nothing more, nothing less.

Absolutely! Now this is the cave in the State Forest, right? Why would the gate be paid for by your grotto and not the state? Not to say that individual cavers, grottos, regions and the NSS itself shouldn't contribute to such things (if appropriate and practical), but usually the ultimate responsibility rests with the landowner - even if it is the state. If they really "don't have the money" there should be federal grants etc available to them.

Another question for you - is the cave entrance vertical? If not, I fail to see the point in using a box gate when a (presumably) much smaller gate inside the entrance will do the job.

I think we're still talking at cross purposes with cave gaters "not giving up their day jobs" - the ones I know, this IS their day job! But they're usually funded by federal/state/private funds and/or grants - not by grottos. They are contracted to construct gates which help PROTECT caves and their natural inhabitants - so I still can't see any caver conflict of interest there.

Again, good luck with the project.

[Cheryl Jones]

Maybe this book would have some helpful information.

Bat Gate Design
Edited by Vories, Throgmorton, and Harrington

Proceedings of Bat Gate Design: A Technical Interactive Forum was held at the Red Lion Hotel, Austin, Texas, March 4-6, 2002.
Topics covered:
Why Do We Protect Mines and Caves?
Project Planning
Closure Design: Part 1
Closure Design: Part 2
Construction Management
Monitoring and Maintenance.
http://www.caves.org/service/bookstore/bats.html Scroll down.

In addition, a lot of good information was presented in Bat Gates for Large Colonies and Maternity Sites (Roy Powers and Jim Kennedy) at the 2005 NCKMS. The paper is included in the 2005 Proceedings (CD and hard copies) Available from the NSS Bookstore and Speleobooks.

[tncaver]

Dan Straley wrote:
"The forest wants the box gate, but I personally want to know it's the right choice. This particular cave has no bats and never has.. until recently no one ever really caved in it.. A new passage was found, which has expanded the cave much further and exposed and aquifer connection. Bat's could use the cave I guess, but it's very tight for a long distance past the entrance".

Dan,
This confuses me somewhat. If there are no bats and never has been and
few people ever enter the cave, why does the forest service want to gate it?
Is it because recreational cavers might have fun in it due to the recent
extension of the cave? Is having fun while caving outlawed? Is there a
legitimate reason for wanting to gate this cave? And like you, I question
why they want to put such a large gate on such a small entrance.
It's been awhile since you posted to this topic. Has your grotto made a
decision about financing this expensive gate that will in essence keep
your grotto members out even though it is on public land? None of this
makes sense to me.
Looking for answers.
Tncaver