Bulletin Board

We would like for you to: We'll put the newer questions on top for frequent visitors and leave the older ones below for newcomers. I am with a utility in Washington State, Benton County PUD, that is considering using spike strips on the wood crossarms and pole tops of our overhead 34.5 kV distribution line. The insulators are post type and the construction type includes neutral up design on 10' crossarm with approximately 37" of phase separation. There is also some neutral down construction on 8' crossarms with the center phase on a pole top bracket and approximately 44" of phase separation.

I do not see much on your website about this type of anti-perching device. We've never used them before, but I was hoping someone was familiar with this method and any comments they may have. The products I've found so far are Bird Spike 2000 from Bird-B-Gone, Inc., http://www.birdbgone.com/birdspike2000.htm and a similar product from Bird-X, http://www.bird-x.com/products/spikes.html. I've seen other products that were stainless steel design, but I am more comfortable putting the polycarbonate plastic design on the crossarm than metal.

I really enjoyed your website, lots of good information. Thank you.

Blake Scherer
Electrical Engineer
Benton County PUD

The utilities we've talked to generally give bird spikes mixed reviews. Some have found them effective, while some have not. There are two problems with bird spikes. More and more birds find they make an excellent substrate for nests. They pile leaves and twigs on the spikes (which anchor them and keep them from blowing away or falling off)until they have a nice base for their nest. In addition, line crews, as a rule, really hate working around bird spikes, especially when they are used in substations. Some large birds will perch on the spikes and just bend them out of the way. (By the way, we don't recommend using metal bird spikes on crossarms in any case.) That being said, bird spikes can be an economical and reasonabley reliable deterrent, depending on the species of bird causing the problem. Let us hear from you and your experiences and we'll see if we can work up a consensus... From our Canadian colleagues... We hope Mark stays in touch and shares his experiences with the rest of us. (P.S. Thanks for the kind words)

Good Day,

Just want to compliment on the web site. Seems like there is lots of good information there -- keep it up!

Also, I'll share with you some of our experiences in Alberta, Canada. Our major problems as far as animal outages are birds; mostly raptors, owls, and especially ravens. Here are a couple photos you can put on the site if you wish. Ed. note...See Photos.

We're currently examining many solutions including apparatus insulation in substations, bird deterrent units, guards, and insulating silicone paint. Wish us luck!

Mark Mielke, EIT
Transmission Facility Management
Phone: 780-420-3441
Fax: 780-420-5410
E-mail: Mark Some suggestions for our colleagues in Columbia...
We also have some ideas we wanted to suggest. You may already know some of these, so we apologize in advance if we're telling you some things you have already considered.

Transmission outages caused by bird "streamers" are, in fact, quite common. The ecosystem you described is ideally suited to creating such a problem. A solid prey base and relatively flat terrain with utility structures dominating the landscape. The fact that you have found virtually no evidence of electrocution is also not surprising. Hawks are relatively small birds and the separation between the energized conductors on an 11.5 foot crossarm (if our math is correct) should be more than sufficient to prevent phase to phase or phase to ground wingtip contacts. Since electrocutions do not seem to be the primary cause of concern, obviously the ultimate goal is to prevent the birds from perching above or near the insulators. However, before installing the combination of remedies we are going to suggest, there are some things to consider.

First, beware of the "Domino Effect", that is, don't create a worse problem by solving the wrong problem first. Realistically speaking, installing deterrents on the structures with contaminated insulators will probably result in forcing the birds to other structures or, more likely, other locations on the same structures. Once most raptors have selected their "preferred" structures, they can be remarkably stubborn about re-locating. Particularly in your case where the birds really have no alternative perching sites.

There are devices that can be installed on the guard wire posts to prevent perching (see the Product Catalog), but we suspect that using those products alone will simply force some of the birds to try and perch on the crossarm. Now you have birds trying to perch on a metal crossarm very near energized conductors, increasing the chances of an electrocution outage. Adding perch guards (see the Product Catalog) will prevent perching on the crossarm, but we think the real problem is the lack of alternative perching sites. Considering the frequency of the outages and the expense of washing insulators, we think the cost of installing safe perches, in conjunction with deterrents on the guard wire posts and crossarms, is certainly justified.

Here in the United States, many utilities regularly install bare poles, crossarms, and platforms near their energized power lines to prevent ospreys from nesting on utility equipment. We think installing deterrents without providing safe alternative perches will simply move the problem to the next available location or just make it worse.

You mentioned photographs in your e-mail, we would love to put them on the web site if you can send any to us. Streamer info...

Dear Colleagues

I used to work at CSIR South Africa where we had program dedicated to research of birds-caused outages.

Actually program was about to simulate mother nature conditions in institiute laboratory. I guess it was one of very few programs that practically and empirically justified strong influence of streamer of birds excrement to the reduction of break down strength of air.

Additional beauty of this program was that we simulated real conditions with real HV line tower as well as laboratory condidtions above 1,000 m. I'm still having a brilliant picture that represents this simulation and break down in air close to the composite insulator at 769 kV LI.

Should you have any additional information please do not hesitate to contact me.

Best regards

Dragan Tabakovic MScEE
Surely by now, we've all had enough experience in dealing with raptor interactions with power lines to offer some help. We're sending our suggetions and we know others out there can help too...

We were recently asked to carry out a very short study (1 week) on transmission lines in the Eastern Plains of Colombia. An oil company there has been experiencing outages since October (over 80) and think that the problem is due to streamers from hawks perching on the utility poles.

Over the week we counted the number of hawks seen perching, hunting from, roosting and defecating on the poles. We also looked for corpses and excrement under the poles. No corpses were found and an experiment to show the rate of disappearance due to carrion feeders showed that corpses remain under the poles in identifiable conditions for a couple of days. An identifiable skeleton was also found that had been there for two weeks according to the workers on site.

Many hawks were seen perching on the poles during the day and night and excrement was found at the base of poles that seemed to match excrement seen to be defecated by hawks at various times.

We include a brief summary and diagram of the poles. We are looking for ideas to prevent the hawks from perching on the guard cable poles.

We have just come back from the field so the results from our study are not ready yet, we also have photos which we could send at a later stage.

We would appreciate any ideas to work on at this early stage and look forward to your and other people's response to this problem.

Best regards,

Christian Devenish and Marķa Isabel Moreno

Click here to see the construction diagram. A response to the question of adding hot peppers to silicone to prevent parrots "chewing" on insulators, from Kam Abeyewardene at BCHydro...
In my very limited experience with pet parrots, very hot, usually green chilies, were added to their diet as treats. The parrots seemed to like these very much. They would chew on the peppers, pick out the inards and discard the rest. I'd be very interested to know the result of adding the hot pepper to the insulating material as a deterrent for these Australian parrots.

We decided to check with our wildlife expert and see what he had to say...
"Adding capsaicin (the active ingredient in peppers) to the silicone is an interesting idea but I'm not sure it will work. I'm skeptical since the active ingredient, capsaicin, is typically effective with mammals, not birds. This is likely an evolutionary adaptation to keep mammals from eating the fruit and the seeds. Birds are the primary means of dispersing seeds, so a clever plant would develop a chemical that rodents hate and birds don't mind."
A while ago we received an e-mail from a young couple in Texas asking about snake fence. The couple has two very young children, an infant and a todler, and were building a house on a small ranch. They were concerned about snakes getting into the yard and said they had planned to build a three foot stone fence with a four-inch overhang. They asked our opinion on the design, which we, of course, responded (at great length). Since then we have had several requests for re-prints of our response, so we decided to post it here as well.

In designing a snake proof fence, try to keep two things in mind. First, snakes are excellent climbers and, second, snakes can get through incredibly small openings. Snakes use a variety of methods for locomotion, but, typically, they move by pushing and pulling the scales on their underside against the ground or any other textured surface. A stone fence, unfortunately, would be very easy for a snake to climb. The four-inch overhang may or may not be sufficient to deter a snake, depending how large and determined it might be. Snakes are virtually all muscle and amazingly strong.

A snake's skull is the largest solid bone in their body, even though their heads are usually much smaller in size than their bodies. Any opening a snake can fit its head through; it can eventually work the rest of its body through. And remember, small snakes can get through very small openings.

There are several more effective designs you could use, although I'm afraid they are very utilitarian in appearance. I have attached a design we recommend for electric power substations. Perhaps you can get someone to modify it for a more pleasing appearance. The key features are: either a very small mesh wire or a very smooth (i.e. metallic or something similar) solid surface, the bottom of the fence well below the surface (at least six inches) and most importantly, the fence angled out 30 degrees with a 45 degree overhang. The tight fitting gates and thresholds are ideal but visually inspect them, keeping in mind what small openings a relatively large snake can actually get through.

Inspect the outside perimeter of your fence and make sure there are no trees or large shrubs close to or overhanging the fence. Snakes also have no difficulty climbing trees. Snakes will enter your yard for food, shelter, or water. If you use grass as a ground cover, keep it cut as short as you can so if a snake does get in, it will be easily seen. Remember a snake's coloration is designed as camaflouge against the natural background. Try to eliminate, if possible, any fixture in the yard that might provide shelter or cover.

Do NOT use a bird feeder or bird bath in the yard, keeping birds out of your yard is absolutely essential. Snakes can't hear but they have a superb sense of smell and, although they don't have particularly acute eyesight, their eyes are excellent motion detectors. It is the motion of birds flying in and out that most often attracts snakes into an enclosure (yard). If you can, avoid planting ornamental trees or shrubs that have fruit or berries that attract birds.

Don't use chemical "home-remedies" or repellents. Aside from posing a real hazard to small children and pets, they really don't work.

Although I'm sure you have warned your children about snakes, children that young don't always really understand the danger. If you haven't already, check with your pediatrician for advice on what sort of First Aid (snake bite) you should keep on hand. Find out which hospitals or clinics in your area keep snake anti-venom on hand. You might even make a few trail runs to the nearest one.

As for the probability of a snake climbing the fence you described in your e-mail, the four-inch overhang is the only thing that might deter a small snake. The stone wall is easily climbed and frankly, I don't think a large, determined snake would have any problem getting past the overhang.

The odds of a snake even trying to climb your fence will depend on what may or may not attract them to your yard. The difficulty is the age of your children. Adults bitten by poisonous snakes almost always survive, but that is not necessarily the case with very young children.

I hope I haven't overloaded you with information, good luck and let me know how it works out. From Rick Harness at EDM International: Does anyone have recent labor cost estimates to install bird flight diverters on static wires for a 230kV or larger line? I'm looking for an installation cost using a crane versus a helicopter. Access along the ROW is good and the line is 18 miles long......

And here are some responses...

Tri-State: Pat Dille said a recent estimate for one of their projects is $65.00 per attachment. They do not feel people on the static wire is safe and it is a remote location, therefore this is for helicopter installation. Pat felt a 33% discount could be expected for using a man lift. An interesting note Pat added is a significant portion of the cost is associated with getting the proper placement of the devices. The present state-of-the-art specifies a 5 meter visual horizontal spacing. Thus for 2 static wires, one wire gets a 10 meter spacing and the the other also gets also gets a 10 meter spacing but staggered midpoint from the other line. The spacing measurements take a significant amount of time in the air....

Public Service New Mexico
From: Rick Precek
Blake Forbes stated he would definitely get a quote from the helicopter guys (like USA Mobile, or Haverfield) to do 18 miles. Crane work is not the way to go for 18 miles(travel and set up will eat you alive), but another way that might work is a modified bosons chair or spacer cart. The line man rolls down the span or is pulled by a guy on the ground.

Montana Power Sam Milodragovich states their engineer is in the field but he remembered the unit cost to install a BFD on a 69Kv line of SAHPC construction was $30 each earlier this year. The bids on other jobs have ranged from $30 to $50. He is bidding a job now using the cable cars to install them and the bid is $35 each. This price does not include the cost of the BFD. From Kevin Eldridge at Midsun Group, Regarding the raccoons climbing the crossarms. We sell a porcupine wire called E/Animal Control Strips (ACS) that can be stapled to the corssarm or wrapped around the pole to turn them. Northeast Utilities has photos of it wrapped around a S/s transformer with raccoon prints climbing the device, finding the E/ACS and prints turning around. We are also making a special ACS for FP&L that has longer spines and spikes and easier to install. See our website at www. midsungroup.com for more details.

Regarding the Australian Parrots nipping and eating the silicone, we are currently experimenting under our own patent pending process to put capsium (hot pepper) into the bulk silicone rubber. Comments about this would be appreciated. From Mike Roe at McCook Public Power District, squirrels and URD, "Use a "Jackmoon" (brand name) duct seal. We wanted to move away from Kellem type support grips on our risers and found the perfect solution in the duct seals. While we weren't trying to keep critters out, we simply wanted something better for mechanically holding the cable in place at the pipe exit. Local suppliers may carry Jackmoon products but if not, call: Ted Dolmat, Jackmoon USA, 550 South Melrose St., Placentia, CA 92670, 800-382-8758." A quick response for our friend with the raccoon problem...(see below) Bob Hartman of Kaddas Enterprises, Inc. writes "we have a product that should solve the marshland raccoon problem. Our BirdGuard lp cover (Editor's note...see the Product Catalog) will protect both the power line and the raccoon and should eliminate any further problem with power outages." If you think squirrels are a problem, read this...
I work for a utility that has part of their overhead lines over marshland. When we have a high tide, the raccoons love the arms on the top of the pole. We have major companies on the end of these feeders that really can not take the hits or outages that they are getting. I am looking for a device that we can put right under the cross arm that will turn them (wraps around the pole). We have something to put on the arm to keep the birds off (plastic) but we have nothing for the raccoons. Some utilities have successfully used wraps on their poles to keep some climbing animals off (but remember, this will NOT work for squirrels). If you want to try using wraps, a low cost remedy, there are two things to keep in mind. First, raccoons are large animals, so wrap enough of the pole to keep them from simply climbing over the guard. Second, raccoons have very sharp claws and very clever "fingers", so the material you select will have to be sturdy enough to keep them from ripping it down. Select a few poles that give you the most trouble, see a contractor or building supplier for the appropriate material, install the guards (with your engineer's approval) and see how well it works. Good luck and let us know what happens. Some help for those with gapped arrestors on single bushing transformers...Thanks to Mike Roe, Director of Engineering, McCook Public Power District, McCook, Ne.
We are experiencing fewer problems of this nature (usually sparrows or starlings "bridging" the gap) since we began removing the gapped arrestor assembly and installing a direct connected MOV arrestor. At the same time, we install a Salisbury bushing cover on the primary bushing, their #38-18SC stinger cover between the bushing and arrestor and stinger cover for approximately 2 feet from the arrestor to the line connection. We top it off with a Kaddas Enterprises Arrestor Cap on the arrestor and the entire transformer high side is covered. How about some help for our International friends? The animals may be exotic to us, but the problems are the same.
Just received an interesting problem arising before the holidays. Seems there is a transmission company in Australia which has been using silicone (as in the plastic) insulators, which seems to be a new trend in the industry as they are cheap and easy to produce, low maintenance. Except big parrots love to chew them to bits (of which there are MANY in Australia). Have any of you run into similar problems of some animal eating silicone insulators in the industry? I am astounded that they are using them here since parrots LOVE plastic and there is enough documented problems with them peeling insulation & ABC conductors around here. I'm looking to see what has been reported and whether anyone has tried any solutions (besides putting in good old tough glass/porcelein insulators back in). Appreciate being able to tap into the collective minds of y'all. Hope you all have happy holidays and a fabulous new year! We really like your web site, it's very interesting and has a lot of information, great pictures, too. But it's also very big, how can we tell when and where you add something new? Oops.....guess what? It's time for another new section. This one we will call "New As Of.....", with the date. We'll list what's been added and where it can be found, that should help frequent visitors keep up. As promised, we have more information on the use of predator urine, courtesy of Ken Libby of Northeast Utilities.

Sorry for the delay, I was off on the trail of SF6 gas leaks and a couple of animal cover-up jobs. Let me try to answer some of your questions. I have been purchasing the repellents from a New England supplier in gallon containers. However, they can be purchased from larger garden centers such as Agway stores. As for your burning question on collecting urine in sufficient quantities, that's the suppliers secret!!! Fox urine makes varmints such as rabbits, groundhogs, woodchucks, squirrels, and chipmunks think foxes are around. Bobcat urine makes varmints like mice, moles, and all types of burrowing rodents think Bobcats are present.

Dispensing Predator Urine - the liquid is placed in a 4oz. plastic dispenser bottle which is then hung on or near the equipment to be protected. The dispenser bottle, when full, should last approximately 4 to 6 weeks, depending on the evaporation rate. (The plastic bottles are filled with cotton and have small holes near the top so the urine odor can vent.) For substations - the dispenser bottle should be placed 18" to 24" above grade, a short length of wire can be attached to the wire loop on top of the bottle and the attached to the equipment. This method allows the bottle to swing freely in the air, dispensing the urine odor 24 hours a day. Bottles can be hung around capacitor frames, reactor stands, breakers, PTs, station service structures, and feeder getaways. An alternative method would be to hang the bottles ever 20' around the fence perimeter. This method should only be used on small substations. Bobcat urine should be hung under raised floors in the relay and control enclosure, 2 bottles are recommended, 3 in a very large building. A short length of wire can be attached to the wire loop on top of the bottle. The bottle is then placed under the raised floor in a convenient location, say in the hole cut in the floor where the control cables enter the duplex panels, A bottle can also be placed around the perimeter of switchgear or in padmount equipment. For distribution systems, dispenser bottles should be placed on locations such as riser poles, pole top capacitors or switchgear where a history of outages exist. When hanging a bottle on a pole, attach a short length of stainless steel wire to the loop on top of the bottle and attach to the pole with a staple. We made a concerted effort a couple years ago to check all the control cabinets and panels for nesting rodents and snakes and actually found quite a few. That dropped our raccoon problem down to nearly zero. We now make sure during station inspections and maintenance that we investigate all potential nesting sites and remove them if they are found. Frank Peverly. We think Frank is from Orange and Rockland Utilities (let us know if that's not right, Frank). In any case he has done what is probably the single most effective (and least expensive) action anyone can take when dealing with this problem. That is, find out what is attracting the animal, then move or remove it. This is one reason why we tend to preach about right-of-way clearing. Thanks, Frank, there are a lot of frustrated utility people out there who can benefit from your experience. We (Vermont Electric Power) have been having lots of trouble with raccoons causing outages. Any help or comments would be appreciated. Raccoons are, indeed, a major headache in the Northeast, particularily in substations. There are several things you can do that might help. If the raccoons are getting in your substations, first try to identify what is attracting them. Usually, it's nesting birds and their eggs, a favorite snack for raccoons. Unfortunately, raccoons are also one of the few animals that will climb through substations just out of curiosity, so you may be having problems for no really good reason. A lot of utilities in your area have used climbing guards mounted on the substation fence with good results. Those with really stubborn raccoons have enclosed their substations with fences made with barn or house siding (installed vertically!). There is a picture of this type of fence on the web site....go to "Search by Device", then "Substations", and then down towards the bottom of the page. If raccoons are getting into your overhead devices by climbing poles, a climbing guard mounted on the pole will usually put a stop to that. There is a picture of this type of guard on the web site....go to "Search by Device", then "Distribution", then "Overhead Devices", and then down towards the bottom of the page. Let's have some more suggestions from our readers. Northeast Utilities in Connecticut has been using predator urine for the past year, with favorable results. We have been using Fox urine for squirrels and Bobcat urine for rodents. Do you have any information or background using scents? So many questions come immediately to mind that it is hard to know where to start. (First of all, to our readers...this is not a joke and Northeast Utilities is not the only utility to use these products.) Now to the questions (we'll post the answers here as soon as we get them)...Where do you get these products? How often do you have to replace them? Do you use them in substations? Do you put them on poles? What about underground equipment? And of course, the most burning question of all, how is the urine collected in sufficient quantities to be available for sale? We are trying to protect our buses from squirrels by covering the bus work. We've used several types of material, including PVC tubing and non-metallic liquidtite slid along the length of the bus. We cover the bus connectors with a clear PVC wrap. Has anyone looked into any derating effect on the bus by covering it up? The derating effect would not be equivalent to the derating factor between indoor and outdoor buses because we still have the effect of the wind. Any help would be greatly appreciated. There is, of course, a derating effect and we are looking up the answer for you. In the meantime, look in the Product Catalog for some ideas. Any suggestions out there? We have had a rash of underground cable failures in our risers due to squirrels chewing on the cables. We have an excellent line clearance program so most risers are free and clear of branches. We have tried duct-seal but that weakens and loosens with age. Stuffing rags, etc. also does not seem to work. I surveyed the North East underground Committee (NEUC) and the members did not seem to have a problem similar to this. Have others had this problem and are there any innovative solutions? First of all, in your part of the country (New York, right?) you may be dealing with flying squirrels rather than the usual tree squirrels. Not that it really matters, of course, it's just that this is a faily common problem with flying squirrels, they love to nest in the conduits on riser poles. Most utilities with this problem have used the following combination with some success: two layers of (steel mesh + foam insulation). Keep in mind that squirrels will chew through almost anything, so you want to use a barrier that is as indestructible as possible. How about some more suggestions from some of our readers? We have been having problems with birds (Ravens) shorting out our Switching/Substations and damaging our Lightning Arrestors/Primary Switch Gears. Our voltages are 34.5 KV/12.47 Volts and all aluminum/steel structures. Our interest is the Bird in Distress Call which would eliminate down time and labor if at all possible. Other suggestions will be greatly appreciated. Without a doubt, there is nothing more frustrating or difficult than trying to keep birds out of substations. There are, indeed, a number of products and devices that utilities have tried over the years, one of which is the Bird Distress call you mentioned. Unfortunately, this type of deterrent is usually only effective for a short period of time. Most birds, particularly ravens, are clever and observant enough to realize fairly soon that there is no real danger and will proceed to ignore the distress call. If this is a chronic problem, that is, the birds are permanent residents in the area and not just passing through, you will have to take more drastic action. Probably the best answer is to concentrate on protecting the equipment and realize it's almost impossible to keep the birds away. In other words, insulate everything you can and use shields and bushing guards where you can't. One more thing to keep in mind...birds are not the only ones that will respond to the distress call. Every predator (raccoons, cats, etc.) within hearing will come running. Bird distress calls are dinner bells to hungry predators and you may end up with a worse problem. If you would like to talk about this some more, e-mail us your phone number and we'll be happy to give you a call. What is that on the cover of the manual? We can't make it out. Maybe an enlargement will help. This is an incredible photograph taken by Billy Brownshoes, a lineman with Clay Electric (Illinois), and yes, it's a fox. As the story goes, Mr. Brownshoes spotted the fox on the pole while driving to work. A large dog at the foot of the pole was the apparent explanation for the fox's unbelievable climbing ability. A classical example of the saying, "fear lends wings to the feet".Getting the fox down was another matter. After tying the dog, Mr. Brownshoes climb the pole and managed to snare the fox's tail with his hot-stick. After trying unsuccessfully to pull her off, he finally resorted to pushing her off and grabbing her legs as she started to fall. Mr. Brownshoes climbed down with the fox and released her, untied the dog, and drove to work. Not a light blinked. We are having a problem with transformer outages in one of the older residential areas. It happens mostly at early evening during the summer so we don't think it's squirrels. Once we found feathers and once we found a dead bird, but there aren't that many birds out at night. What else could it be? We know we shouldn't answer a question with a question, but...Do these transformers have gapped arrestors? Are the street or security lights on the transformer poles using mercury vapor lights? If so, the problem could be insects. Mercury vapor lights have a blue band that attracts insects and insects attract night-feeding birds and bats. Insects flying or crawling through a gapped arrestor can cause an outage and leave no clue to what happened. Some utilities have so much trouble with insects that they are replacing their transformers with conventional ones. If you're not ready to take such drastic action and insects do seem to be the problem, first try replacing the mercury vapor lights with high-pressure sodium. Does anyone else have a suggestion?

(Editor's note...we originally had this question on our Raptor page, but we got such a quick response - like 5 minutes after we started notifying folks this Web site was online - we decided to move it here)"Buzzards" are European hawks, and they do, indeed, look like hawks. How the name "buzzard", here in the United States, became attached to the vulture is a mystery (if anyone out there knows, please tell us), particularly since there is absolutely no resemblance between the two. We call vultures "buzzards" because the first Europeans thought they were seeing soaring hawks when they arrived in America. In Europe, hawks are called buzzards. Unfortunately however they were actually seeing storks (New World vultures), but as you know that's another story. Anyhow, we have been stuck with the term buzzard for vultures ever since because of poor taxonomy!
Richard Harness
Environmental Specialist