I am not an arborist so cannot comment on the condition of the trees in relation to a safety risk.
The nesting birds should have been very obvious during the inspection on 2nd June. From the photos I have seen of chicks affected, some of these are more than four days old, so would have been there at the time of the inspection. Regardless, this is a large an active egretry and it is impossible to walk past at the moment without seeing adult birds and chicks in the nest. Even if they are not visible on the branches under discussion, it should be apparent to a site inspector that there would be disturbance from the crane to nearby nests.
The "Guidelines for Tree Risk Assessment and Management Arrangement" referred to in LCSD's statement (
https://www.greening.gov.hk/file ... RAM_Arrangement.pdf) includes the following:
2.6.1 Trees for Sensitivity Analysis
Tree management departments are to undertake Sensitivity Analysis when considering the proposed removal of the following types of trees under non-emergency circumstances:
OVTs;
Stonewall trees; and
Trees of particular interest, such as rare species or trees of cultural significance.
Examples of trees of particular interest are listed as below for reference:
Rare tree species listed in ‘Rare and Precious Plants of Hong Kong’ (http://herbarium.gov.hk/PublicationsPreface.aspx?BookNameId=1) published by Agriculture, Fisheries and Conservation Department.
Endangered plant species protected under the Protection of Endangered Species of Animals and Plants Ordinance (Cap 586).
Well-known Fung Shui trees.
Landmark trees with evidential records to support the historical significance of the trees.
Trees which may arouse widespread public concerns.
Trees which may be subject to strong local objections on removal.
It does not seem to explicitly include anything about protecting animals using the tree, but I would argue that the site inspectors should have been aware that pruning the tree may 'arouse widespread public concerns' or 'may be subject to strong local objections on removal'. Also, given that the egretry is well documented, they could be considered 'Landmark trees'. Thus, I think that it would have been appropriate in this case to assess the situation further before proceeding with removal.
I would suggest that one action the HKBWS could take is to ask for a strengthening of these guidelines to take into account the impacts to wildlife. It seems appropriate that any tree management should take into account the impacts not only to nesting birds but also to other affected wildlife (e.g. bats, especially fruit bats in palm trees) and should avoid wildlife impacts as far as possible.
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Last edited by ajohn at 8/06/2017 14:38 ]
