You start the game with a horse, and it is the single biggest quality-of-life change from older Harvest Moon games: whistle and the horse appears next to you wherever you are, so the size of Teradea stops being a problem. The whole Harvest Moon: Echoes of Teradea mounts roster has to fit four whistle slots and eight barn spaces.
Harvest Moon: Echoes of Teradea mounts and the four whistle slots
| Mount | Where | Skill |
|---|---|---|
| Starting horse | Bloomfield | — |
| Silver Dapple Horse | Near the top of the Trailhead, before the bridge into White Horse Ridge | Bunny Jump |
| Dromedary Camel | Great Sand Sea | Cold Tolerance |
| Reindeer pair | A short distance east of the Quarrytop Campground | Cold Tolerance |
The whistle has 4 mount slots. Assign a mount to a slot and it comes when you whistle, and assigning one mount per environment is the practical setup — a camel for the desert, a fast horse, a jumping horse and a reindeer for the ice.
The Silver Dapple Horse and Bunny Jump
The Silver Dapple Horse has the Bunny Jump skill and is found near the top of the Trailhead, just before you cross the bridge into White Horse Ridge. You need a mount with a jump ability for the large chasm on the road to Quarrytop, and the Silver Dapple Horse is the fallback if you have not found anything better — but you need free barn space to tame it.
The scale of it: 96 Jump-Off Point spots need a mount with a jump ability, spread across Bloomfield (44), Quarrytop (27), Maplehill (8), the Great Lava Cavern (8), Tidewind (4), the Harvest Goddess Forest (3) and the Desert (2). On foot those are simply walls, and the cave systems they lead into are on the dungeons page.
The camel, the reindeer and cold tolerance
The Dromedary Camel is the desert mount. It can run across the shifting sand rivers of the Great Sand Sea and reach corners you cannot otherwise get to, including the Quicksand Labyrinth ore cave in the desert's south-west corner. Its downside is that it refuses to run at night without the Cold Tolerance skill — once 7:00 pm rolls around its speed drops to a stubborn crawl.
The Reindeer is the ice mount. A pair of them can be befriended a short distance east of the Quarrytop Campground, they cross icy ground without sliding the way you do on foot, and one of them is needed to travel north along the icy path to the island in the middle of the lava lake that holds a Ruby Gemstone ore node.
The camel also takes up a coveted barn slot when you only have 4 whistle slots and 8 barn spaces, so plan the roster before you tame rather than after.
The four whistle slots
Four slots and eight barn spaces is not much, so the roster needs a decision. The common end-game setup is one mount per environment: a camel for the desert, a fast horse for general travel, a jumping horse for the cliffs, and a reindeer for the ice.
When you need to swap one in, board the animal you are not using at the Animal Center rather than releasing it — boarded animals keep levelling up and you can collect them again when you have space. The whistle assignment itself happens in the barn book, which is also the roster of everything you own, and how to tame something worth putting in a slot is on the pets page.
When a mount gives up on you
A mount's stamina takes a hit if it triggers a wild-animal alert, and enough hits means it gives up, pulls "Later, loser!" and returns to the farm animal barn. That is how you can end up stranded in a remote region with no way home.
The countermeasure is to bring a mount with a stamina-recovery benefit into predator country, and to keep a Hot Mushroom in your bag: carrying one protects you from the cold for around 30 minutes. Other confirmed companion benefits are cold tolerance and the ability to drive off hostile wild animals.