Wales' environment body, Natural Resources Wales is accused of failing in its duties over tree planting. We hear why a decline in Wales' otter population is a "wake-up call" about the state of the UK's rivers. Essential path maintenance or "environmental vandalism" - the row in Snowdonia to repair a mountain path. We explore the new buzz word of "resilience" in agriculture. And in our series on declining bird species, we hear about the mixed fortunes and folktales of the Rook.