August 7, 2018
To Whom it May Concern:
Re: Active Bald Eagle Nest at Croydon Drive X 20th Avenue., Surrey, BC
Please be aware this incident is currently under investigation by the Conservation Officer Service and City of Surrey for possible charges under the B C Wildlife Act (Section 34), and City By-Laws. This letter has been written completely separate from those investigations and may have no bearing on any future actions taken by the Conservation Officer Service, City of Surrey, or any other agency involved with investigations.
- To document wildlife values lost as a result of multiple unlawful/vandalism acts and subsequent required felling of Croydon Drive Bald Eagle nest tree.
- Provide a recommendation for nest tree replacement.
- Provide long term habitat protection recommendations for a vegetated disturbance buffer to surround an artificial eagle nest structure.
This letter is in response to the recent vandalism and cutting of a mature Black Cottonwood (Populus trichocarpa) tree which has been documented to support an active and productive Bald Eagle (Haliaeetus leucocephalus) nest for nearly a decade. This long-standing productive Bald Eagle nest has a documented record of annually and consistently producing higher than usual numbers of young than known continent-wide average. The loss of this nest represents a major loss for Lower Mainland resident Bald Eagle productivity.
The nest is highly visible and well known in the local community. It has generated extensive numbers of public calls of concern to ministry staff because its location immediately adjacent to the edge of cleared lands that are being readied for urban and industrial land developments.
This Eagle nest structure and the tree it is located within, is protected by the Wildlife Act, Section 34 (b ), year-round. A functional disturbance buffer surrounding the nest tree is also recommended by “Best Management Practices for Raptor Conservation During Urban and Rural Land Development in British Columbia”.
City of Surrey Arborist concludes that this tree was in perfect health, without structural compromise what-so-ever, prior to an initial attempt some months ago to fell it and subsequently again in late July. As a result of these activities, the tree was rendered nonviable, still standing, but precariously balanced upon faller’s wedges when discovered. City of Surrey has characterized this – 60 year-old tree as a “specimen quality tree” – ‘best of the best’. As such, it could have been expected to have supported Eagle nesting activities for many decades into the future.
This particular cottonwood tree had a very fortuitous branching configuration that provided optimal nest anchoring opportunities by having sound and substantial branch “crotching” configuration. Healthy branch crotches are a critical prerequisite to the long-term stability of Eagle nests. Nesting Eagles that occupy established nests iteratively add new materials on top of the previous years’ nest structure. Over time, this results in massive structures weighing hundreds-to-thousands of pounds. For sub-optimal nest trees, these heavy loads, during frequent wind and storm events can prove destructive for both the nest, occupants, and for the branch anchoring structures of the tree itself. The Croydon nest tree exemplified optimal nest construction characteristics and contained a nest structure approximately seven feet across and three to four feet deep.
Availability of suitable Eagle nest trees ( size, maturity, location, branching configuration, proximity to sufficient and reliable food sources, and the ability to defend the nest from intrusion by rival pairs of Eagles), are some of the prime habitat attributes that determine nest site selection. The Croydon nest site has been successfully used by the territorial pair of Bald Eagles for many years, suggesting that this tree and surrounding area provided ideal habitat attributes. This tree was one of the last remaining trees within this Eagle territory that could be considered as a suitable nest tree candidate; thus, options for the territorial pair to relocate and select another tree are limited within their defended territory.
Urbanization within the surrounding area and within the territory of these Eagles has cumulatively contributed to loss of many large, potentially suitable Eagle nesting trees. Given the low availability of suitable nest trees in the immediate vicinity, I recommend this nest tree site be the focus of immediate efforts to erect an artificial eagle nesting structure at the same location, of proven design and configuration. This replacement will attempt to provide some measure of compensation for loss of the original nest tree. Full compensation for the loss of a living, functioning, Bald Eagle nest tree of “specimen quality” value is practically impossible. However, viable, proven, and functioning man-made alternative nesting structures are possible though.
Removal of this nest tree at this time of year (very late July), was ‘accidentally fortuitous’ as nesting season chronology for most resident Lower Mainland Bald Eagle pairs has just ended. Thus, the territorial pair should be out of the general area now and consequentially disturbance minimized from mitigation measures and activities. And so, opportunities to replace the nest site with a functional structure are optimal as far as seasonal timing. If an artificial nest structure can be erected in time for onset of local pair’s territory seasonal defense and occupation by mid-September 2018, transition for the pair could potentially be ‘near-seamless’. As such, time is of the essence for replacement of the destroyed nest. Artificial nest trees have been successfully and comparably carried out in other areas; e.g. multiple years of recent Eagle nesting success in a man-made structures at several Lower Mainland locations.
Of equal value to the actual structural integrity and branch configuration of the nest tree is a functional buffer of trees surrounding the nest tree to minimize disturbances. To affect such a functional buffer, a land polygon of sufficient and prescribed extent, size and habitat attributes must be established and protected in perpetuity. Achieving completely functional, long term screening by adjacent trees and vegetation at this site, in its current damaged condition from the felled nest tree, is likely to require restoration and augmentation. The area set aside for the mitigated nest should be the subject of a comprehensive, long term habitat management plan prepared by a qualified environmental professional that is a specialist and well-versed in Eagle nest tree and disturbance buffer habitat attributes.
SUMMARY OF RECOMMENDATIONS:
- Replacement of the nest tree structure at the same location as the felled nest tree to accepted and proven design criteria.
- Erection of an artificial Eagle nest structure on site by mid-September 2018.
- Establishment of a permanently protected buffer surrounding the nest structure of
- Protection of a comprehensive Eagle nest area habitat management plan established by a Qualified Environmental Professional and approved by Ministry of Forests, Lands, Natural Resource Operations and Rural Development (FLNRORD).
- Establishment and restoration of screening vegetation to prescribed design criteria, to restore a functional disturbance buffer for the nest site.
- Ongoing monitoring and assessment of developed infrastructure and habitats for a period of ten (10) years.
- Ongoing maintenance and refinements for nest structure and vegetated buffer as determined necessary by FLNRORD.
Resource Manager, Stewardship,
South Coast Natural Resource Region