Taking From Nature

Maybe it's just a coincidence, but I received the credit from the Burning Ascent Fishing Hole Net after crafting the Iskaaran Harpoon with Tavio in Iskaara and get the Cutting Tusk Equipment achievement.

Reaching level 4 Renown with [faction=2511] will unlock the River Mouth Fishing Hole in the southeast of The Waking Shores. Once you have this unlocked, you'll be able to complete Flying Fish each day, and will have the option to complete Otter Devastation daily to unblock the [object=382070] at that location.

The second weekly active Fishing Spot around the Dragon Isles, including Grimtusk's Fishing Hole in the mid-east part of The Azure Span, Roaring Dragonspring Fishing Hole in southeastern Ohn'ahran Plains, Burning Ascent Fishing Hole in the west side of The Waking Shores, and Tyrhold Fishing Hole in central Thaldraszus undergoes a weekly rotation. You will know which fishing hole is active by the presence of a fish symbol present on the map at the respective fishing hole. The second "active" fishing hole for will be selected randomly from the following options (thank you to Viriya for the correction on this being random):

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• Roaring Dragonspring Fishing Hole
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• Burning Ascent Fishing Hole
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• Grimtusk's Fishing Hole
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• Tyrhold Fishing Hole
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While Flying Fish will remain an option to complete each day, if you want to earn progress for this achievement, you'll need to venture to the other active fishing hole for a given week at least one of the days and complete the appropriate unblocking quest for that fishing hole. Note that you can only complete one unblocking quest per day, so if you choose to do the one at the River Mouth Fishing Hole, you won't have the option to do the one at the other site on that given day. As noted by @sipder2, the required quest for each site is as follows:

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• Roaring Dragonspring Fishing Hole: Predator Control
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• Burning Ascent Fishing Hole: Frogs of Fire
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• Grimtusk's Fishing Hole: Net Worth
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• Tyrhold Fishing Hole: Underwater Menace
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You will be able to complete the daily quest that has you collect fish with the [item=198855] and release them each day at both locations without risk of losing your ability to unblock the Fish Net. Completing both of these daily is a good way to earn progress towards Giving Back to Nature/Giving More Back to Nature/Giving Even More Back to Nature since these quests count as 20 restocked fish, where the unblocking quest counts as 10 daily. For more information, see those achievements' pages.

One day we'll get Grimtusk's :')