October 30, 2012 at 1:15 pm
As the nights continue to get colder, wild animals all over the state are making preparations for the impending winter. For otters, this means increased marking of fishing territories so other otters know where their neighbors will be fishing when ice forms. I was invited to accompany one of our wildlife biologists as he searched for the elusive otter latrines (bathrooms).
At 6:30am, the air was thin and cold, the grass supported a mild frost, and it was still quite dark, a sure-fire sign of the bittersweet end of summer. As 7:00am approached, we were launching the Old Town canoe on the Little Androscoggin River with nothing but pictures of otters and scat dancing in our heads. The sun was rising as we paddled along, stopping to check any place an otter might scurry up the bank to mark, and as is the case on most of Maine’s rivers and streams, the combination of early morning sun light, autumn leaves, and fog lifting off the water created some dream-like, wonder-inspiring views. It was a glorious morning for a paddle, which is good, because the scat left by marking otters was significantly more elusive than we imagined it would be!
The river otter surveys are a blooming study MDIFW is conducting in different parts of the state. The idea is that an estimate of the river otter population can be extrapolated by surveying for latrines either in the spring or in the fall when otters are marking more than usual, staking out their fishing and/or breeding grounds. A survey is done once early in the season, counting the number of latrines found and marking their locations on a GPS. The survey is re-conducted a week or two later, again counting the number of latrines and marking their locations. It is similar to a count-recount method in which you can use the difference in the numbers between the first and second surveys to get an idea of the density of otters in a specific area. Unfortunately for us, this method of counting otters is only viable if scat is being left where it can later be found by biologists, and we did not happen to find any otter scat on this particular six mile section of water trail on this particular day.
This is the first year that MDIFW conducts river otter latrine surveys of this type and, as with any study method, it still needs some breaking in. The lack of otter scat does not necessarily mean there are no otters (in fact, scat was found on the first survey of this same section). It simply means the otters that are there may not be actively marking. There are multiple reasons for the lack of marking scat found: they could be marking and we just weren’t looking in the correct places, they could be there and not marking (although this is unlikely, given the season), or they could be currently utilizing a different section of their territory. Otter home ranges, or the area that they spend most of their time in, can be ten miles or more long. It is possible the otters were there the week before but had moved to a different section of their range by the time we re-surveyed the area.
While the lack of finding active otter latrines was a little disappointing, as it is whenever you don’t find what you’re looking for, it was a beautiful day, I had the opportunity to learn a lot about otters from our field biologist, and I had the opportunity to snap some pictures on one of Maine’s beautiful water trails. Let’s face it, any day spent canoeing and learning new things is always a good day, whether you find what you’re looking for or not!
At 6:30am, the air was thin and cold, the grass supported a mild frost, and it was still quite dark, a sure-fire sign of the bittersweet end of summer. As 7:00am approached, we were launching the Old Town canoe on the Little Androscoggin River with nothing but pictures of otters and scat dancing in our heads. The sun was rising as we paddled along, stopping to check any place an otter might scurry up the bank to mark, and as is the case on most of Maine’s rivers and streams, the combination of early morning sun light, autumn leaves, and fog lifting off the water created some dream-like, wonder-inspiring views. It was a glorious morning for a paddle, which is good, because the scat left by marking otters was significantly more elusive than we imagined it would be!
The river otter surveys are a blooming study MDIFW is conducting in different parts of the state. The idea is that an estimate of the river otter population can be extrapolated by surveying for latrines either in the spring or in the fall when otters are marking more than usual, staking out their fishing and/or breeding grounds. A survey is done once early in the season, counting the number of latrines found and marking their locations on a GPS. The survey is re-conducted a week or two later, again counting the number of latrines and marking their locations. It is similar to a count-recount method in which you can use the difference in the numbers between the first and second surveys to get an idea of the density of otters in a specific area. Unfortunately for us, this method of counting otters is only viable if scat is being left where it can later be found by biologists, and we did not happen to find any otter scat on this particular six mile section of water trail on this particular day.
This is the first year that MDIFW conducts river otter latrine surveys of this type and, as with any study method, it still needs some breaking in. The lack of otter scat does not necessarily mean there are no otters (in fact, scat was found on the first survey of this same section). It simply means the otters that are there may not be actively marking. There are multiple reasons for the lack of marking scat found: they could be marking and we just weren’t looking in the correct places, they could be there and not marking (although this is unlikely, given the season), or they could be currently utilizing a different section of their territory. Otter home ranges, or the area that they spend most of their time in, can be ten miles or more long. It is possible the otters were there the week before but had moved to a different section of their range by the time we re-surveyed the area.
While the lack of finding active otter latrines was a little disappointing, as it is whenever you don’t find what you’re looking for, it was a beautiful day, I had the opportunity to learn a lot about otters from our field biologist, and I had the opportunity to snap some pictures on one of Maine’s beautiful water trails. Let’s face it, any day spent canoeing and learning new things is always a good day, whether you find what you’re looking for or not!Categories