Critical Period means the time of year when the special timber operations practices set forth in these regulations are required to minimize nesting disturbance to a species of special concern.
-California Forest Practice Rules
Species of Special Concern include Bald Eagle, Golden Eagle, Great Blue Heron, Great Egret, Northern Goshawk, Osprey, and Peregrine Falcon. Species of Special Concern are not the same as Threatened and Endangered Species. T and E species rise to a much higher standard of protection. They are protected under rules originating from the Endangered Species Act.
When a nest site of a Species of Special Concern is identified in a timber harvest plan area, a buffer zone is established around it. The buffer zone sizes differ according to the species. The critical period is based on the nesting season for that particular species of bird. No timber harvesting is allowed within the buffer zone during the critical period. After the critical period, harvesting can take place, but the nest trees are always retained. There are limitations as to the type of harvesting that can take place in the buffer zone, such as no clearcutting is allowed. The harvesting practices allowed in the buffer zones are tailored to each species. depending on their needs.
The Northern Goshawk fledgling in the picture was discovered after my crew and I stumbled onto a nest tree. We were marking trees when one of the guys came and informed me he saw a “great big bird in a nest.” When we went to investigate, I could see right away it was a Northern Goshawk fledgling, and there wasn’t one, there were two.
The young birds were branching. This is when they hop from branch to branch strengthening their wings before they have mastered flight. We stopped marking and began moving away from the nest. One of the Goshawk parents was nearby but moved away from us. This was a relief because Goshawk parents are well known for attacking people that are too close to their nest. This usually happens when the chicks are very young. Apparently, they are less protective when the chicks are older. We watched the young birds from what we thought was a safe distance, so as not to spook them. Then, one of the youngsters glided out of the nest to a branch in a nearby tree. Its sibling, not wanting to be left alone, followed. Only this bird wasn’t as advanced in its flight training as the first. It glided downhill and smacked straight into the trunk of a white fir tree and tumbled to the ground. I told the crew, “Oh my God, I think we just killed it.” Fortunately, it popped up on its feet, screeching all the while.
I sent the crew to mark timber in a different area. Then, with my camera in hand, I headed down the hill to check the condition of the young Goshawk. It was mad as hell and ready to give me what for. Otherwise it was okay. I took a few pictures and backed off to let it calm down. I knew, at this age, it would be able to hop its way back up the trees to safety. The parents weren’t far away and would tend to it.
For the Northern Goshawk the buffer zone is twenty acres and the critical period is from March 15 through August 15. The forester who prepared the timber harvest plan knew the Goshawks were living in the plan area. He protected their nest tree, by making it a no harvest area. However, the uncooperative goshawks had decided to move out of a perfectly good nest and build a new one in the logging unit. We were the first to discover the new nest. As a result, a new twenty acre buffer zone was established around this nest and none of the trees we marked in the area were harvested.
The buffer zone for the Osprey is 5 acres and the critical period is from March 15 through August 15.
If harvesting is done with a helicopter, they can operate no closer than one quarter mile of the nest tree. This is true for Bald Eagle, Golden Eagle, Northern Goshawk and Osprey. Peregrine Falcon get a one half mile buffer.
The herons and egrets have a 300′ buffer around nest trees. Their critical period goes from February 15 through July 1.