Work Restrictions in Occupied Habitat
If marbled murrelet surveys (using the 2003 USFWS survey protocol or the most updated version of this guidance document; Evans Mack et al. 2003) determine that the project area is occupied, or if USFWS presumes marbled murrelet occupancy without conducting surveys, the Project Proponent will adhere to the following Protection Measures. Surveyors are required to meet or exceed all training recommendations in Evans Mack et al. (2003) or the most updated version of this guideline document.
a. Vegetation Removal or Alteration of Known or Potential Nest Trees:
i. No potential marbled murrelet nest trees will be removed during any time of year. Potential habitat defined as: 1) mature (with or without an old-growth component) and old-growth coniferous forests; and 2) younger coniferous forests that have platforms (relatively flat, at least 4 inches in diameter, and at least 33 feet above the base of the live crown of a coniferous tree). Platform presence is more important than tree size.
ii. Removal or damage of known or potential nest trees will be avoided. Project Proponents should seek technical assistance from the USFWS for known or potential nesting trees determined to be a “hazard tree,” or otherwise identified for possible removal to implement the project. For sites that have not been surveyed according to 2003 survey protocol, potential habitat is defined as: 1) mature (with or without an old-growth component) and old growth coniferous forests; and 2) younger coniferous forest that have platforms.
iii. Removal or damage of trees with potential nesting platforms will be avoided. A platform is a relatively flat surface at least 10 centimeters (4 inches) in diameter and 10 meters (33 feet) high in the live crown of a coniferous tree. Platforms can be created by a wide bare branch; moss or lichen covering a branch; mistletoe, witches brooms, or other deformities; or structures such as squirrel nests.
iv. Project activities will not alter suitable nesting habitat to the extent that it is no longer functioning.
v. Trimming or pruning of unsuitable nest trees or limbs, trimming or removal of
brush, and felling of hazard trees in suitable habitat may occur outside of the nesting
season.
b. Auditory, Visual, or Other Disturbance:
i. No proposed activity generating sound levels 20 or more decibels above ambient sound levels, or with maximum sound levels (ambient sound levels plus activitygenerated sound levels) above 90 decibels (excluding vehicle back-up alarms), may occur in confirmed marbled murrelet nesting habitat during the majority of the murrelet nesting season (i.e., March 24 through August 5) (USFWS 2020a).
ii. Between August 6 (date when most murrelets have fledged in coastal northern California) and September 15 (end of murrelet nesting season) of any year, project activities, with adjacent suitable nesting habitat, that will generate sound levels ≥10 dB above ambient sound levels will observe a daily work window beginning 2 hours post-sunrise and ending 2 hours pre-sunset. However, prep work that does not generate sound levels above ambient sound levels, including street sweeping and manual removal of pavement markers, can occur during all hours. The need for this daily work window depends on the distance between suitable nesting habitat and the above-ambient sound generating activity following USFWS’s guidelines (USFWS 2020a). For example, if above-ambient sound levels generated by proposed activities will become attenuated back down to ambient sound levels prior to reaching suitable nesting habitat, the daily work window would not be necessary
iii. The sound level restrictions mentioned above will be lifted after September 15; after which USFWS considers the above-ambient sound levels as having “no effect” on nesting murrelets or dependent young.
iv. No human activities shall occur within visual line-of-sight of 100 meters or less from a known nest location within the Action Area (USFWS 2020a), or from unsurveyed suitable nesting habitat containing potential murrelet nest trees within 100 meters of proposed activities.
v. Not to exceed the self-imposed take limit of injury or mortality to no more than one nesting murrelet pair and their dependent young (one egg/chick per annual clutch) per recovery unit.