When you’re in the “Explore” tab of the main page, make a border around the map or add another “non-map” area so, when in the Map tab, you can scroll up and down without making the map zoom in and out.
The Projects page has a border around the map in the Map tab, so that could be used as a model. Or an ideal place might be to the right of the list of observations since it seems unlikely anyone would use that area to navigate the map.
EDITED: I noticed that not all Project pages have the border around the map so that is not a valid comparison. But the area to the right of the Observations, I think, would still be a reasonable “scrolling” area.