Post by oksaradt on Sept 30, 2008 9:05:04 GMT -5
Water HRD vs Water Cross-Trained Dog teams
Over the years I’ve been at odds with the popular method that SAR dogs are taught to do water recovery work at seminars. The popular method is the “scent machine” and sometimes buoys on pulley systems that are allowed to pop up to get the dog’s visual attention. The “scent machine” is a contraption that Bill Tolhurst gets credit for though it’s been refined many times over the years.
The scent machine is a sealed container that one can place human remains in. Clean air is forced into the container and “scented air” is pushed out the other side into plastic tubing stretched out into the water to a specified place. There the “scented air” bubbles up to the surface and out into the air above the water. Dogs can be worked from shore or from a boat using the scent machine. When they get close, the buoy is released to pop up from the water giving the dog a visual attaboy. The down-side with the scent machine as well as Water-Psuedo (a tablet that puts out something like cadaverine gas into the water for 45 minutes) is they create an air borne gas for the dogs to hit on. This is why cross-trained dog teams love this training, the dogs pick it up with noses in the air. The downside to this is you can get a lot of “false hits” with strong winds and/or white caps. Dog teams mark their “best guess” as to where the drowning victim with their buoy. It’s depressing to have to be utilized to go out and tell a fire department to yank 10+ buoys all spread out over a body of water. The divers were happy though as the waters were full of barbed wire and junk that put their lives in jeopardy. Rarely do bodies put off active bubbling gasses. If they did, we could just look on the surface where we think someone might be. The gasses come off the body a little bit at a time. More importantly, the body puts off oils such as that which makes adipose tissue. Oil separates from water, so it will float up to the surface and reside as a slick on the surface.
So, why is my way any better? I’m not sure if it’s better. My dogs and the other handlers I work with have had great success with this way of training versus the scent machine or airborne method. I’m sure there have been handlers that trained the scent machine way that have made finds as well. I do recall a seminar I attended early on concerning water searches. The dog was to get you close, then they’d use underwater cameras to locate the body. There’s a small problem with that in Oklahoma, we only have one lake that’s truly clear. The rest are very cloudy due to silt. The instructor that came to Oklahoma to show us this camera kept slapping the monitor claiming something was wrong. They were in my boat at the time and it was all I could do to not laugh as I’m looking over the side at the clay-colored water.
When the search team I belong to works a water death, we drop multiple buoys systematically to locate where the oil slick begins. Using the dogs as scent detectors and working the boats with the wind in mind, our end result actually looks like an arrow in the water with the end point being as close to the body as we can determine using the dog. Accuracy using this method as been as close as the body coming up and hitting the boat the trooper was parked in overnight till recovery work could occur the next day.
So, how does one train the HRD dog to do water work. The more I train dogs for this, the more I begin to see water as simply an easy buried problem. This is why I wanted Murphy versed in buried teeth before starting him on water. Often one of the tests my dogs (and I) have been subjected to is finding a tooth or teeth in shallow water, still or moving. If a dog can locate teeth in water just like teeth in soil, the oil off the body is easy.
So, how do I decide where to look for the body in the first place? The oil slick is moved downwind or by surface water currents till it hits shore. At that point you can deploy dogs along shore. The dogs will indicate when they can’t reach the source out in the water. The handler pays attention to the width of the area of shore the dog has scent in and uses the dog to locate the strongest point in this swath. At that point the handler takes a back-azimuth with a compass into the wind (or perpendicular to the water travel) and radios this into base. As different teams radio in their back azimuths, an intersection can be drawn which determines where on the body of water to search with a dog in a boat.
In the boat, the dog is basically a scent “light bulb”. As a handler, this can be the most fun searching one does because you get to watch your dog’s facial expressions when you take it into scent. Before the dog gets into scent, it should basically be bored with the boat ride. If a dog is stressed in a working boat, it’s not much use to anyone, so acclimation rides should be done before ever training with the dog in scent. My dogs usually have almost gone to sleep till we hit scent then they become very animated. There’s one expert that trains water searching with divers in the water and wants the dogs “used to it.” This is the way she started out. For a singly-trained HRD dog, this doesn’t matter as they don’t look for live. For cross-trained dogs this could be a problem. In Oklahoma waters, it’s not as many of our lakes can be dangerous enough for dive teams without worrying about a dog team tacking across their waters up above.
So, what’s the secret? Sorry, no secret, but lots of repetitions of training, again in baby steps where you start out in 4 inches of water with bone/teeth (after successful buried teeth in soil at the same depth). The dog finds ten consecutive times. You double the depth. The dog quickly reaches a depth it can’t walk in and reach the scent source. At this point, the dog has to reach a point where it indicates the closest spot above the source. At this point, you can start using adipose tissue sources in deep water to train the dog from the boat and shore. The sources I use, I place a small amount of adipose tissue in a large mat of human hair in a PVC tube with lots of holes to allow water flow through the tube without losing the hair inside. As the adipose coats the hair, this source can be used for multiple trainings. Some groups will raise a flag about bio-hazards in the water. Yet people laugh when kids wiz in the same lakes, cut their feet on rocks, etc. Nothing I put in the water harms anyone. Usually, the lake I train in has had many bodies found in it over the years and people are not supposed to swim in it anyway. I’ve yet to see a HazMat crew come out to deal with the body recoveries or jet-ski enthusiasts with a look of joy coming over their face as they stand still in the water for a few moments.
My method is not something you can learn in a weekend seminar as it’s based on foundation training, but I have set out water problems for advanced dog teams at seminars that were readily workable by those dog teams. Labs are prone to diving out into the water and circling over the source….that’s just labs.
To spell out how I work a water problem in a boat once we know the general area. I ask for a boat driver that can tack into the wind in a 45 degree angle to the wind such that the boat engine exhaust is not blowing into the dog’s nose.(I prefer jon boats as the dog gets close to the water on the front bow plate and you can get into a lot of areas.) I tend to do three-four passes tops on setting buoys. Always my goal is to mark where the scent STOPS. We’re going into the scent, so the dog should be animated and suddenly either stop or the dog will walk the boat back trying to stay with the scent. I drop a buoy as close to the point where the scent originates as possible. I’ll try to set another buoy on the other side of the scent cone created by scent/oil movement. If there is no wind and the water is not moving, then you should have a circular oil slick to deal with. This is worst case and means your body should be near the center with an anticipated radius of the slick being equivalent to the depth the body is at.
So, I drop two buoys going by the dog’s loss of scent. My next pass will be again in the wind tacking again to aim between the first two buoys. We should find the dog loses scent a bit more upwind or upstream. If the slope is definitive, we can confirm this by taking the boat upwind and coming back into scent at the point we believe is the most upwind surface point. At that point we drop one more buoy which should be the point of the arrow pointing at the scent source origination point. If the slope isn’t definitive, we might do one additional into the wind pass to place six in-to-the-wind buoys and one with-the-wind-buoy. Dax has made multiple (very accurate) finds using this method over the years.
I trained Tempe with this method and was teaching at a seminar where they set up a scent machine/buoy system one afternoon. I decided to succumb to temptation and let her work it. I spent 3 months after that one afternoon breaking her of thinking the buoy was the scent source. I DO NOT LIKE VISUAL DOGS. Needless to say, even though Tempe had the better nose, L.E. preferred to use the old lady, Dax, for water work as she could care less about floating buoys and was much more definitive about her finds. L.E. love to see a dog barking her indication. Dax puts on a good show. *shrug* This was a factor in wanting a bark on Murphy….mistake dog (Tempe) changes handler/trainer’s mind on the next dog.
I should note about streams/rivers/floods. My attitude is that working HRD from downstream in these conditions sets you up for lots of inaccurate targets. It’s not the dogs fault as this is what happens. The scent flows down stream at the mercy of the water speed. The scent hits a bush, rocks, a tree, etc and rolls against that object placing more scent on that object than is in the water around it. The dog perceives a higher concentration of scent and deduces that this must be a source. I have done flooded river searches where I informed L.E. of this phenomena up front. Some time they just can’t get you up river to the Point Last Seen and you have to work it from down river. One search comes to mind where multiple teams worked multiple days. As the river level receded, objects that were flagged at water level but now up in the air no longer held any interest for the dog. Once the river level receded enough to work it safely from a boat, we entered upstream of the Point Last Seen and the search was much more manageable.
Talking with investigators that have worked drowning victims a lot over the decades, a common consensus is that the bodies rarely go very far from the Point Last Seen unless they started out on flotsam to begin with. So, with that in mind, I advise any search team working a dog for a river drowning to work the beaches as close as possible to the Point Last Seen. If your dog has scent there, there isn’t much reason to continue searching down stream unless you think you have multiple victims, the body was torn apart, or your area experienced additional flooding conditions that you believe would have moved the body again. In the last case, I really have trouble believing you’d still have scent in that Point Last Seen unless the body was there enough time to have decomposed into the soil. In that case, you’re probably searching for disarticulated remains and it’s going to be a very long search.
Hope this helps,
jim
Over the years I’ve been at odds with the popular method that SAR dogs are taught to do water recovery work at seminars. The popular method is the “scent machine” and sometimes buoys on pulley systems that are allowed to pop up to get the dog’s visual attention. The “scent machine” is a contraption that Bill Tolhurst gets credit for though it’s been refined many times over the years.
The scent machine is a sealed container that one can place human remains in. Clean air is forced into the container and “scented air” is pushed out the other side into plastic tubing stretched out into the water to a specified place. There the “scented air” bubbles up to the surface and out into the air above the water. Dogs can be worked from shore or from a boat using the scent machine. When they get close, the buoy is released to pop up from the water giving the dog a visual attaboy. The down-side with the scent machine as well as Water-Psuedo (a tablet that puts out something like cadaverine gas into the water for 45 minutes) is they create an air borne gas for the dogs to hit on. This is why cross-trained dog teams love this training, the dogs pick it up with noses in the air. The downside to this is you can get a lot of “false hits” with strong winds and/or white caps. Dog teams mark their “best guess” as to where the drowning victim with their buoy. It’s depressing to have to be utilized to go out and tell a fire department to yank 10+ buoys all spread out over a body of water. The divers were happy though as the waters were full of barbed wire and junk that put their lives in jeopardy. Rarely do bodies put off active bubbling gasses. If they did, we could just look on the surface where we think someone might be. The gasses come off the body a little bit at a time. More importantly, the body puts off oils such as that which makes adipose tissue. Oil separates from water, so it will float up to the surface and reside as a slick on the surface.
So, why is my way any better? I’m not sure if it’s better. My dogs and the other handlers I work with have had great success with this way of training versus the scent machine or airborne method. I’m sure there have been handlers that trained the scent machine way that have made finds as well. I do recall a seminar I attended early on concerning water searches. The dog was to get you close, then they’d use underwater cameras to locate the body. There’s a small problem with that in Oklahoma, we only have one lake that’s truly clear. The rest are very cloudy due to silt. The instructor that came to Oklahoma to show us this camera kept slapping the monitor claiming something was wrong. They were in my boat at the time and it was all I could do to not laugh as I’m looking over the side at the clay-colored water.
When the search team I belong to works a water death, we drop multiple buoys systematically to locate where the oil slick begins. Using the dogs as scent detectors and working the boats with the wind in mind, our end result actually looks like an arrow in the water with the end point being as close to the body as we can determine using the dog. Accuracy using this method as been as close as the body coming up and hitting the boat the trooper was parked in overnight till recovery work could occur the next day.
So, how does one train the HRD dog to do water work. The more I train dogs for this, the more I begin to see water as simply an easy buried problem. This is why I wanted Murphy versed in buried teeth before starting him on water. Often one of the tests my dogs (and I) have been subjected to is finding a tooth or teeth in shallow water, still or moving. If a dog can locate teeth in water just like teeth in soil, the oil off the body is easy.
So, how do I decide where to look for the body in the first place? The oil slick is moved downwind or by surface water currents till it hits shore. At that point you can deploy dogs along shore. The dogs will indicate when they can’t reach the source out in the water. The handler pays attention to the width of the area of shore the dog has scent in and uses the dog to locate the strongest point in this swath. At that point the handler takes a back-azimuth with a compass into the wind (or perpendicular to the water travel) and radios this into base. As different teams radio in their back azimuths, an intersection can be drawn which determines where on the body of water to search with a dog in a boat.
In the boat, the dog is basically a scent “light bulb”. As a handler, this can be the most fun searching one does because you get to watch your dog’s facial expressions when you take it into scent. Before the dog gets into scent, it should basically be bored with the boat ride. If a dog is stressed in a working boat, it’s not much use to anyone, so acclimation rides should be done before ever training with the dog in scent. My dogs usually have almost gone to sleep till we hit scent then they become very animated. There’s one expert that trains water searching with divers in the water and wants the dogs “used to it.” This is the way she started out. For a singly-trained HRD dog, this doesn’t matter as they don’t look for live. For cross-trained dogs this could be a problem. In Oklahoma waters, it’s not as many of our lakes can be dangerous enough for dive teams without worrying about a dog team tacking across their waters up above.
So, what’s the secret? Sorry, no secret, but lots of repetitions of training, again in baby steps where you start out in 4 inches of water with bone/teeth (after successful buried teeth in soil at the same depth). The dog finds ten consecutive times. You double the depth. The dog quickly reaches a depth it can’t walk in and reach the scent source. At this point, the dog has to reach a point where it indicates the closest spot above the source. At this point, you can start using adipose tissue sources in deep water to train the dog from the boat and shore. The sources I use, I place a small amount of adipose tissue in a large mat of human hair in a PVC tube with lots of holes to allow water flow through the tube without losing the hair inside. As the adipose coats the hair, this source can be used for multiple trainings. Some groups will raise a flag about bio-hazards in the water. Yet people laugh when kids wiz in the same lakes, cut their feet on rocks, etc. Nothing I put in the water harms anyone. Usually, the lake I train in has had many bodies found in it over the years and people are not supposed to swim in it anyway. I’ve yet to see a HazMat crew come out to deal with the body recoveries or jet-ski enthusiasts with a look of joy coming over their face as they stand still in the water for a few moments.
My method is not something you can learn in a weekend seminar as it’s based on foundation training, but I have set out water problems for advanced dog teams at seminars that were readily workable by those dog teams. Labs are prone to diving out into the water and circling over the source….that’s just labs.
To spell out how I work a water problem in a boat once we know the general area. I ask for a boat driver that can tack into the wind in a 45 degree angle to the wind such that the boat engine exhaust is not blowing into the dog’s nose.(I prefer jon boats as the dog gets close to the water on the front bow plate and you can get into a lot of areas.) I tend to do three-four passes tops on setting buoys. Always my goal is to mark where the scent STOPS. We’re going into the scent, so the dog should be animated and suddenly either stop or the dog will walk the boat back trying to stay with the scent. I drop a buoy as close to the point where the scent originates as possible. I’ll try to set another buoy on the other side of the scent cone created by scent/oil movement. If there is no wind and the water is not moving, then you should have a circular oil slick to deal with. This is worst case and means your body should be near the center with an anticipated radius of the slick being equivalent to the depth the body is at.
So, I drop two buoys going by the dog’s loss of scent. My next pass will be again in the wind tacking again to aim between the first two buoys. We should find the dog loses scent a bit more upwind or upstream. If the slope is definitive, we can confirm this by taking the boat upwind and coming back into scent at the point we believe is the most upwind surface point. At that point we drop one more buoy which should be the point of the arrow pointing at the scent source origination point. If the slope isn’t definitive, we might do one additional into the wind pass to place six in-to-the-wind buoys and one with-the-wind-buoy. Dax has made multiple (very accurate) finds using this method over the years.
I trained Tempe with this method and was teaching at a seminar where they set up a scent machine/buoy system one afternoon. I decided to succumb to temptation and let her work it. I spent 3 months after that one afternoon breaking her of thinking the buoy was the scent source. I DO NOT LIKE VISUAL DOGS. Needless to say, even though Tempe had the better nose, L.E. preferred to use the old lady, Dax, for water work as she could care less about floating buoys and was much more definitive about her finds. L.E. love to see a dog barking her indication. Dax puts on a good show. *shrug* This was a factor in wanting a bark on Murphy….mistake dog (Tempe) changes handler/trainer’s mind on the next dog.
I should note about streams/rivers/floods. My attitude is that working HRD from downstream in these conditions sets you up for lots of inaccurate targets. It’s not the dogs fault as this is what happens. The scent flows down stream at the mercy of the water speed. The scent hits a bush, rocks, a tree, etc and rolls against that object placing more scent on that object than is in the water around it. The dog perceives a higher concentration of scent and deduces that this must be a source. I have done flooded river searches where I informed L.E. of this phenomena up front. Some time they just can’t get you up river to the Point Last Seen and you have to work it from down river. One search comes to mind where multiple teams worked multiple days. As the river level receded, objects that were flagged at water level but now up in the air no longer held any interest for the dog. Once the river level receded enough to work it safely from a boat, we entered upstream of the Point Last Seen and the search was much more manageable.
Talking with investigators that have worked drowning victims a lot over the decades, a common consensus is that the bodies rarely go very far from the Point Last Seen unless they started out on flotsam to begin with. So, with that in mind, I advise any search team working a dog for a river drowning to work the beaches as close as possible to the Point Last Seen. If your dog has scent there, there isn’t much reason to continue searching down stream unless you think you have multiple victims, the body was torn apart, or your area experienced additional flooding conditions that you believe would have moved the body again. In the last case, I really have trouble believing you’d still have scent in that Point Last Seen unless the body was there enough time to have decomposed into the soil. In that case, you’re probably searching for disarticulated remains and it’s going to be a very long search.
Hope this helps,
jim