That kind of conclusion takes much more walking the same trails over and over and in the end -- while you can never be certain the animals are absent -- you can at least focus your long-term monitoring effort on areas where you are more likely to find them.
We took a 40-minute ferry to Weggis, stopped at the tourist information center for a map, and then began walking up the same trail Mark Twain took over 135 years before.
"I walked the same streets.
A walk on the same trail on Nov. 4, however, found a member of the Connecticut National Guard, armed with an M-16 rifle, turning away people before they got too close to the plants.
In walking the same jungle trails, getting mugged by the same fierce heat and sleeping in the same simple bush villages, I discovered why Greene wrote that his was "altogether a trip that altered life".
Tomorrow, we would walk a mile and a half down to the Colorado River, before returning to our campsite and hiking out on the same trail the next day.
Run the same trail backwards if you don't live close to many nature trails.
One group walked the "trail of tears" to Oklahoma.
