Satellite Tagging Observation Reports
6/3/01 - After a little over a week, I have some location information on "Gray" the gray seal that was released on May 24 from Cape Elizabeth, Maine, by the Marine Animal Lifeline (thanks guys)...
So far...it looks like we may be in for a tough time. In general, however the first week or so is usually difficult. It seems that for some reason (likely the seal is moving quickly and erratically) we do not get many location "hits" immediately after a seal is released. So far we have been getting one or two locations per day from "Gray", but over the past day or so, it appears to be improving (a bit). We may also not be getting as many signals because "Gray" is not sending as many. If a seal is spending a lot of time peering around at things (with his head up and tail down), the tag will not clear the water well and is not likely to send very many signals. If this is all that is going on, the good news is that if the seal hauls out, we will get many more signals, and at least know where and when he might be out of the water. So far, there is not indication that "Gray" has been out of the water, although he has probably been within sight of the coast.
Briefly...The first few signals in this group are from me testing the tag...(no "Gray was not in Boston Harbor). His first post release point put him at the entrance to Portland Harbor. It is hard to say how accurate that location was, and certainly that was not the direction that we wanted him to go. However over the next several days, Gray headed down (that would be north along the coast) the Maine coast getting as close as a mile or so, to shore and as far as fifteen to twenty miles offshore. He seems to be mostly staying ten miles or so offshore over moderately deep water, and moving slowly along the coast. His most recent positions put him roughly off the coast (about 15 miles off the coast) of Jonesport, Maine.
What do we expect? Well...there are groups of gray seals both to the north and south of his release location (off of islands east of Cape Cod...and along the coast of Maine). The largest groups of gray seals are located off of the east coast of Nova Scotia. It is possible that Gray was born in any of these places. So far he has passed by an area where gray seals are found (Mt. Dessert Rock) and is near the mouth of the Bay of Fundy. To do this, he is probably swimming against the prevailing and tidal currents in the Gulf of Maine.
What might be next? Well, this may be a rough ride...He may head north into the Bay of Fundy, east around the coast of Nova Scotia, or West towards the coast. If he heads to the coast in this location, he will be in an area heavily populated with fish farms...not a good place to be if a seal is going to stay out of trouble.
So...keep your fingers crossed...hopefully we will be getting more data...and we can keep you up on his latest moves...
6/8/01 - Well this could be more difficult that planned. So far we are getting signals from the tag on Gray, but have had fairly few good location fixes. We appear to be getting a day or so of good locations, then a day or so with no locations. We have had similar problems tracking other seals in this area, and have generally written it off to rough sea conditions. Our latest locations (from a day ago) show Gray near the center of the mouth of the Bay of Fundy. This is an area of strong tides and currents, and may be having an effect of the way he is swimming (which , in turn is making it difficult for the tag to send good signals). This is just a guess, but it seems to be supported by the pattern of signals we are getting. We may be getting better transmission on days when he is headed in one direction, and poor transmission when he is headed in another direction. Ifthis is the case, it would also mean that he has been changing direction frequently or circling. At this point only time (and some luck) will tell.
Keep your fingers crossed....I am still getting signals as of today, so I know the tag and Gray are still out there...somewhere...
6/11/01 - Hmmmmmmmm. No one said this would be easy. We are continuing to get a slow trickle of data from "Gray". It still appears that we are having a couple of problems, it appears that "Gray" is not sending many signals. This is probably due to his posture in the water, making it difficult for the tag to clear well enough to send a signal. This is common when seals are first released and I think it may be because they are spending a great deal of time at the surface with their head up (and the tag down, below the water). Also, it may be that he is traveling erratically. This tends to confuse the satellite when it is trying to locate the signals on a pass. The evidence for this is that we have had several locations reported with low LC values, but that were based on a greater number of signal "hits' than one would expect.
In any case, our most recent locations (such as they are) show that "Gray" has turned around and begun heading south again, likely along nearly the same path he moved north. his last position was roughly nine miles north and east of Mt. Desert Rock. The Rock is a well known seal haul out for both harbor and gray seals.
We will see over the next few days if he heads to this haul out.
6/13/01 - More data from Gray. Such as it is. Gray is still proving to be a tough seal to follow, but we continue to get a few locations each day. His most recent locations put him roughly twenty miles from the nearest land...a small island named Matinicus Island. The nearest coastal landmark is probably Rockland Maine (home of Andre the seal), which is about fifty miles to the west of Grays most recent location.
What is interesting, is that this is near one of the first few location hits we received as Gray headed north. The cluster of locations over about twelve hours probably means that he is hanging around this area (possibly looking for food). We will see if he continues to stay near this area. The nearest landmark is an area known as "Skate Ledge"...I suspect a good area for finding Skate (which gray seals have been known to eat).....
6/20/01 - More locations from "Gray" who is still proving a tough seal to follow. We continue to get two or three locations per day, but we have had a few gaps where we are getting signals but no locations. Most of this appears to be because the satellite is only getting one signal per pass from the tag. Unfortunately we need at least two (and the more the better) signals in order to calculate a location. Most likely this is because "Gray" is swimming in such a way that the tag is not clearing the water enough to get off a good signal. The good news from all of this is that if that is the case we should be getting signals for a long time, because the tag is saving battery power by not signaling frequently. It also means that since his release, (one month ago, this Sunday), "Gray" has not yet hauled out. I can be pretty sure of this, because if he were to haul out we would get a flood of signals and locations from the tag. So far "Gray" appears to be keeping within 10-15 miles of the coast and moving parallel to the coast along a (roughly) 100 mile section of mid-coast Maine. The center of this area is MT.Desert Rock, which interestingly enough, is a known area where gray seals haul out. Our latest locations put "Gray" heading north along the coast about 25 miles north of "The Rock". If he continues in this area is MT.Desert Rock, which interestingly enough, is a known area where gray seals haul out. Our latest locations put "Gray" heading north along the coast about 25 miles north of "The Rock". If he continues in this direction he will head into the Bay of Fundy. If he turns around, he will retrace his path back down the coast (for a second time). If he takes a right turn, he will head towards Nova Scotia, and a left turn will head him into the coast. Hopefully we will see which way his path takes, in the next few days. 6/22/01 - Latest locations from "Gray". We continue to get a few locations per day, which would appear to indicate that "Gray" has yet to haul out (Sunday will mark the one month mark since his release). In the past day his behavior appears to have changed a bit and he had moved closer to shore and appears to be following the coast moving north. His most recent location put him roughly one to two miles offshore near the town of Cutler, Maine. Hoping he keeps away from the fish farms in the area..
6/26/01 - Almost exactly one month after he was released, it appears that "Gray" has hauled out. Over the past two days we have gotten signals from "Grays" tag that indicate that he is on shore on a small set of ledges roughly 8-10 miles southeast of Grand Manan Island (Canada). This location is in the same general area that he visited several weeks ago, however at that time he stayed further to the east and in deep water. Signals from his tag place him on a small ledge (named Yellow ledge), which is a part of the Murr ledges. It appears that he has been out of the water long enough to cause the tag to shut off. The tag is programmed to shut down once it is out of the water for six hours, to save battery power when a seal hauls out. Hopefully "Gray" will return to the water and we will see where he heads from here.
If you look closely at the data, you will see that the "LC" or location code increases (from "A" or "B" class to class 3...the highest accuracy class) when "Gray" gets to shore, because of the large number of signals sent, when he is hauled out.
7/3/01 - Latest from Gray. Still having some trouble with few locations. It seems like this is a tag problem, as the tag is sending some strange status information back. We will see if we can figure out what the problem might be...
Meanwhile, "Gray" is moving again, and no longer hauling out. His latest positions seem to show that he is heading back towards the coast of Maine and is about 20 miles away from the coast at this point. He still appears to be making a large looping track around the northern part of the gulf of maine.
Hopefully we will see if he continues this pattern. Keep your fingers crossed...
7/5/01 - Latest data from "Gray", now over a month since release. As we are getting only about one or two locations per day, it is a bit difficult to figure out any fine scale movements, but it appears that he is staying near (within ten miles or so) of the area he was last hauling out (Murr ledges). It is unlikely that he has been hauling out for the last week or so (or we would have gotten some messages from the haul out areas).
7/10/01 - The latest from Gray. Over the weekend, it appears that "Gray" headed towards the small island of Petite Manan, just off the Maine coast. Our most recent locations show him hauled out on the northern edge of this island. It has been a day or so with no messages, however, this does not seem to be unusual for this seal that we seem to be having a good deal of trouble keeping track of.
7/16/01 - The latest set of locations from "Gray". Over the weekend "Gray" has continued to stay near the coast of Maine. He appears to be moving between the small islands in this area, occasionally hauling out for a few hours on some of them. His most recent locations are from near the mouth of Prospect Harbor , Maine and the last location shows him apparently hauled out on Schoodic Island (north of Bar Harbor, Maine along the coast). We will see if he stays near the coast, or once again heads across the Gulf of Maine, towards Nova Scotia.
7/18/01 - For the past two days, "Gray" appears to have stayed near Petite Manan island, and occasionally hauling out (note the LC 1,2 and 3s). When he is in the water, he appears to be staying in water that is close to the same depth that the other gray seal we are tracking "Sputnik" is staying near, on the other side of the Gulf of Maine....interesting...
7/19/01 - Latest locations on "Gray". Pretty much the same story for the past few days. Locations are centering around a haul out area on Petite Manan Island, just off of the Maine coast. Although close to shore this area has quite a few areas of deep water near the coast and may small islands and rocks that can be used as haul outs. As "Gray" appears to be spending a bit more time out of the water, we have been getting better locations each day.
7/23/01 - Here are the latest locations from "Gray". For the past few days it appears that "Gray" has stayed close to the same location, centering around Petit Manan Island. Since he appears to be hauling out more frequently we are getting more location fixes. And those that we are getting tend to be quite accurate (check the LC). It is a bit hard to be sure how much he is traveling between haul outs, as we still get few locations while he is swimming. His most recent location if it is true, shows that he has moved north along the coast to a location near Jonesport, Maine. We will see over the next few days if this means that he is changing locations, or if this is simply a short side trip.
7/28/01 - Latest from "Gray". Our most recent locations show that "Gray" is continuing to stay in the same general area generally around Prospect Harbor, Maine. He has been ranging around a small area near the northern coast of Maine for the past couple of weeks. It appears that he is not traveling far from sure (although it is difficult to be absolutely sure) and has been returning ot one of several locations to haul out.
8/3/01 - Latest from "Gray". The locations from over this weekend show him to still be in pretty much the same area. He appears to be centering on two haul out locations and moving around in an area about 10 by 20 miles in diameter....he has been in this area since the early part of July.
8/15/01 - Anyway...some seals like to live in the fast lane...take chances...go to places no seals in their right mind would go (see "Sputnik"), SOME seals just like to hang around the same old rocks and hang near the coast. The latter would be "Gray". When we last left "Gray" he was hanging around the north coast of Maine (near the town of Jonesport). During the past couple of weeks he has...well pretty much stayed in the same general area and done the same general thing. His big trip was a couple of day run up the coast nearly to the Canadian border and back (about 50-60 miles each way). While this is the biggest move he has made in some time, it is pretty small moving compared to some (again, see "Sputnik" for comparison). What IS very interesting about being able to watch both of these seals at the same time are the differences and similarities in their behavior. Although one is moving around a great deal and the other is not, they are both staying (for the most part) in similar depths of water). It is also quite interesting, that, although they could have moved closer together (as in...headed to the same habitat), they seem to be staying on opposed sides of the Gulf of Maine.
In another couple of weeks it will have been three months of tracking for Gray. We hope we will be getting another month or so of data, but after the third month it will be anybodies guess as to how long the tag will last....
8/20/01 - Well Gray just keeps going. And now something new!...Over the past two days "Gray" has headed away from the location he has been near for the past month or so. He has headed south following along roughly twenty miles off of the coast. His latest location puts him roughly due east of his release location in southern Maine (about forty miles offshore). The next few days should be interesting to see if he continues to the south or heads back along a similar track to the one he followed after his release.
9/7/01 - Well the good news is that I have a lot of data to dump after a week away. The not so good news is that it appears that we have lost transmission from "Gray". Our last message came from 9/2 (Sunday) so it does not appear to be a temporarry pause in messages.
Generally when we lose signals it may be because the tag stopped signalling, the tag fell off, or something happned to our seal. This one is a little strange, because "Gray" appeared to be behaving as expected (not wandering or moving randomly). The tag was not showing signs of malfunctioning (they seldom do), but the tag was getting towards the end of its battery life. This track lasted 101 days, which is still less than other similar tags, So tis is a possibility, but not my first chioice. This would leave the possibility that the tag simply fell off. Not impossible, but not very likely at this stage either. That leaves something unexpected happening to the seal. Unfortunately there would be no way to be sure of this (unless someone finds him and the tag, which is also unlikely). So we are left with a bit of a mystery.
Map of "Gray's" travels.
More seal data is available in the current WhaleNet Listserv. Sort and go to FIND for "Seal Data", "Gray" entries.