Nesting birds and tree workers

[moss]

For tree workers active bird nests are a tricky situation. The Federal Migratory Bird Act makes it illegal to disturb most species of actively nesting birds in the United States. Enforcement is very low but the law is enforceable by state and federal environmental police. Like a lot of laws on the books enforcement happens only in the most egregious cases or when an onlooker calls in a complaint. It's on the tree worker to assess and be aware of birds nesting in hollows or in branches and limbs before starting and during work.

To say that tree work shouldn't happen during bird nesting seasons is a broad overreach, mainly out of ignorance. It certainly comes from the perspective of caring but is inaccurate. Tree work will happen across the entire bird nesting season and that season is very long in most places.

For example in Massachusetts great horned owls start laying eggs in late February and Cooper's hawks are hatching young in mid-June. Goldfinches and cedar waxwings nest very late, often in mid-summer. Throughout the month of May nesting by many species is widespread and nearly unavoidable in tree work depending on the scale of a job.

The level of expertise required to know what's nesting where and when, in what types of trees, etc etc. is beyond what most of us can determine. Even the experts will have trouble locating a screech owl nest in a mature oak full of hollows and the small openings accessed by these owls. There are obvious cases, many birds will make a lot of noise and show agitation when workers get near nests

The best response from tree services after damaging an active nest site is to contact local animal control and/or state environmental police. No one gets fined if they report craning out a tree part or whole tree and baby hawks spill out on a front lawn when the tree is put on the ground. The point of the law is to encourage responsible behavior. Multiple times the rehabilitators I work with have contacted me to build new nests and put babies back after tree services did the right thing and called for assistance. In several cases federal or state environmental police were involved and no prosecution happened.

It's pretty obvious that generally speaking wildlife and the environment often lose out when money is at stake. If more of us do our part to find a way to do less damage to wildlife it's a good thing.

https://www.fws.gov/law/migratory-bird-treaty-act-1918 (has been updated/modified many times since it was first passed)

-AJ

 

[ghostice]

I was working on buncha spruce this spring getting rid of deadwood and scragglers - on one of the tree trunks was a small birdhouse. When I started on that tree Mama Nuthatch made a great amount of noise and went up (headfirst) and down (headfirst upside down) the trunk. As soon as the noise became loud and steady, a nesting Merlin would start cruising and the Nuthatch would become quiet. I delayed doing that tree for a month. It was amazing to watch the interplay between the two bird species. Never thought that "Butt Out Mister" calls from one might call in a predator species so quickly. Nature is very cool . . . . .

 

[climbingmonkey24]

Thanks @moss, this is a great post!

 

[Serf Life]

Quality and always nice to hear people who are ethical and decent. Sadly/disturbingly that is often not the case.

 

[moss]

Additional thought, I mentioned reaching out to animal control officers ACO's and environmental police. If you already know local rehab resources for small mammals, small birds or larger birds like crows and raptors, that's a go-to to get started dealing with a situation. Problem is they're always overwhelmed during nesting seasons and can be slow to respond. ACO's and environmental police usually know who to go to rehab-wise and will often take the weight off and establish communication with them so you can stay focused on your job.
-AJ

 

[southsoundtree]

I ziptied a limb with nest and 3 eggs to another limb after finding it too late.

 

[moss]

I ziptied a limb with nest and 3 eggs to another limb after finding it too late.

Mileage varies per bird species but typically eggs are a fairly low investment vs. the perceived danger of predation. Whether it's a raccoon poking around at a nest or a climber in close proximity the parents will often abandon ship and nest somewhere else so they can reduce chances of another predator visit.

It was definitely a creative and worthy attempt to ziptie the nest and eggs to another spot, gave the parents options.

The crazy part is that once the young are hatched the parent's fidelity to them is over the top persistent. You could probably run a saw within feet of a nest and as soon as you go away the parents will be right back to continue feeding their young. So many variables, if workers stay all day or several days in trees around nests it will be much more difficult for the parents to overcome their fear and keep up with taking care of their young.

Corvids like bluejays, ravens and crows are a whole different matter. They're way too smart compared to say hawks and owls. Nest rebuilds and placing young back in doesn't work for them. Their sense of danger is sophisticated and everything appears like a trap to them where humans are concerned. Crows will accept fallen young back into a nest they built. It's pretty interesting what some species of birds will or will not accept related to nest interventions.

I'm not "the authority" on this subject, I know what I know from years of doing this work and de-briefing with rehabilitators after dealing with a wide range of disturbed nest situations. Always new things to learn about bird behavior, there's still a lot that is unknown.
-AJ

 

[ghostice]

I still remember a job where we were working some spruces and one of them had a magpie nest (around here there are literally clouds of them to the exclusion of all other bird life). When the stem and branches/ large nest (condo?) hit the deck, a whole bunch of magpies congregated over the magpie young on the ground/ brushpile and proceeded to devour them piece by bloody piece, even with all the guys around. Grossed us all out, that did. I love most bird species but around here, most people figure the best magpie is a subspecies called a flatpie and it's endemic to roadways . . .