Grey-crowned Babbler. Response to SIS 2005, prepared by Cumberland Ecology for the Dept of Commerce
Grey-crowned Babbler (Pomatostomus temporalis) Vulnerable, TSC Act
by John and Patricia Edwards to SIS 2005, prepared by Cumberland
Ecology for the Dept of Commerce
Clarence Valley Regional Water Scheme
The grey-crowned babbler received no consideration whatsoever by studies for the initial EIS. However, as it is a recently-listed species, some work has now had to be undertaken by Cumberland Ecology (CE) for this SIS.
Nevertheless the work achieved for this species is extremely limited. CE's records of sightings of grey-crowned babbler appear to have been gleaned by a simple check of the NSW Wildlife Atlas, and by even more simple guesswork. Apparently there has been a single sighting of grey-crowned babbler in the Chaelundi National Park; two in Nymboida NP, which could have been the same family group, and apparently no less than 5 detections by Friends of Shannon Creek Action Group from the Koukandowie Nature Reserve in 2004 (Part f - 8-part test, Vols A, B & C)
(*Note: These Koukandowie records are fabricated, and must be discounted. The only visitation to Koukandowie by members of FOSCAG was in 2002, during which visit no grey-crowned babblers were seen, or recorded.
Table 5.3, p5.23 Vol 2, states that the babbler is known to occur "within the locality" of the Koukandowie Nature Reserve. This also would seem to be not quite the case, being borne out by map Fig C.2, Vols B & C, Appendix C, which indicates an absence of records of grey-crowned babbler on the Koukandowie Nature Reserve. There is clearly no recorded identification of grey-crowned babbler within the Koukandowie NR.
Hence we have just 2 known sightings of grey-crowned babbler within the most immediate local reserves.
CE does admit that data (presumably gathering of) for grey-crowned babbler was limited by the duration of the surveys (Vol 2, p5.32). This is no excuse for guesswork, which CE also uses in assuming by these records that, " ...given the proximity of these records it is likely that this species also occurs in the Chambigne NR."
As Nymboida National Park is 20km to the north west, and Chaelundi a similar distance to the SW, with no known records of the babbler in between - not even within the northern midway Ramornie NP - the suggestion that these groups could be somehow inter-related is seen as nonsense.
(*Note: In an extended exploratory period (1979-2005) the grey-crowned babbler has never yet been recorded within the Chambigne Nature Reserve. [Edwards & Edwards]. This is not to state it is definitely not there, but only to suggest that the species needs to be seen before being recorded as definitely present, otherwise caution suggests it might well not be.)
Although CE was restricted by time, and even more restricted by knowledge of the babbler, its requirements, and its whereabouts, he nevertheless concludes that "...Given the lack of known habitat within the study site and the restricted extent of clearing required, it is unlikely that the species will be subject to significant impacts from the proposed Storage Facility and the pipeline." (8-part test Vols A, B & C, pB.165, Background notes).
Both the admitted lack of known habitat and the supposition of no significant impact could well prove dangerous for the Shannondale babbler family group. CE concedes the species' presence in the area, although he hasn't seen them. Presumably this was acceptance of long-term study and records of the group by P Edwards (1979-2005), incorrectly accredited as recorded by Alison Martin (Greenloaning Biostudies, 2003). CE also admits that the birds' habitat will be cleared by the access road, but then, contrary to his background notes, asserts that the babbler, "... is expected to survive in the study area in the long term because of the retention of large areas of habitat..."
Again CE presents very little other than sheer guesswork to support this supposition. There is no scientific study, and no suggestion - not even guesswork - for the possible cause of the babbler's extremely limited occurrences in what appears to be an apparently healthy environment, nor of the relatively unknown domino effect that any clearing of previously undisturbed habitat may have.
In earlier studies the babbler was recorded approximately 2km east of the Coutts Crossing village, and in two sites along the Orara River approximately 1.4km apart, which could have been the same family group. The northernmost sighting on the Orara is the closest known group to the Shannondale population, with 4.8km of mostly cleared grazing land and rural residential properties separating the two.
Without information of the number of birds within the Orara River family group, it is considered likely that the Shannondale and Orara groups are two separate families, rather than the one mobile family. It is feasible that these two families could meet and intermingle for breeding purposes, but given the birds' preferred habitat and with no recorded sightings in between, this seems unlikely to be happening at this stage.
This deduction also contains an element of guesswork similar to CE's, but it is also based on long-term knowledge of the Shannondale population. ... (Section deleted as irrelevant. The status of Grey-crowned Babbler is currently under review by the NSW Scientific Committee).
The Compensatory Habitat Management Plan, Table 2.2, p 2.7 suggests there is 111ha of suitable habitat for grey-crowned babbler within the study area (Vol I, 6.3.2. Overview of Conservation Status of Subject Species, p6.8), and shows the babbler to fall within the hillside eucalypt open forest habitat category. Yet there is no support evidence supplied for this assessment of 111ha, and no further mention of grey-crowned babbler in the Compensatory Habitat Management Plan. It should be assumed that if the 111ha is genuinely suitable for the babblers, then the species would be resident in that area. Yet none have been seen.
Again, contrarily, Part (a) of the 8-part tests finds that "...As this bird species is known to forage and live within a wide variety of forest and woodland types, the 3,500 hectares of land within the buffer and the compensatory habitat will provide extensive areas of potential habitat area."
Other negatives for grey-crowned babbler by the SIS include:
1) The Phytophthora cinnamomi Plan of Management mentions grey-crowned babbler only by Table 3.6, p3.18, but by this mention the species' presence within the study area is questionable. The likelihood of impact to the species by Phytophthora infection receives a C, and consequences of infection receives a D. There is no explanation of the code letters C and D, but CE finds the risk to grey-crowned babbler by Phytophthora infection to be low.
(*Note: By earlier documents CE also found the risk of introduction of Phytophthora cinnamomi into the Shannon Creek area to be low. However tests have since shown positive for the pathogen within North Coast Water's lands pertaining to the proposed dam.)
There is no specific assessment of habitat preferred by grey-crowned babbler, therefore no consideration of the susceptibility of components of this habitat to infection by the pathogen. Grey-crowned babbler receives no other mention by the Phytophthora plan of management. There is no mention of babbler by the Black Swamp Plan of Management, and only a single notation of babbler by the Shannon Creek Restoration Plan, as a simple inclusion in a footnote listing of fauna assemblage of the dry coastal foothills.
2) Vol I, Table 3.3, p3.9, considers the babbler in a little more depth, but finds the likelihood of impact to the species by all components of the proposed project to be low, although a potential risk nevertheless. Then, again contrarily, CE finds (Vol B p6.3) that clearing of woodland and open forest, and of wetter coastal swamp sclerophyll forest for the access road will be the major cause of impact to the grey-crowned babbler. By this it can only be deduced that the babbler is an affected species, and the likelihood of impact is high (Vol B, p3.8, Table 3.3). Unfortunately there is no evidence of research, discussion, or access to local knowledge to support either of these assumptions.
Equally as contrarily, Vol I, Table 6.4, p6.17, (Importance of known populations of Threatened Fauna), gives the species a single star, deciding its status to be scarce and infrequently seen. Yet the same table claims this babbler population to be ... "a sizable and viable occurrence of high conservation significance," and that the birds in this area "... form part of a larger population that extends beyond the study area."
Vol I, Table 6.6, p6.23, depicts "at least" 408 records on the NSW Wildlife Atlas, and shows scattered occurrences from Ballina to Woolgoolga, Muswellbrook to Nelson Bay, and from Goondiwindi to Mudgee. There is no follow-up research to ascertain dates of these records (ie whether the populations are current, or whether the birds might have long disappeared from now developed land). There is also no mention of the numbers of birds within each family group (whether the group is viable or not), nor if some sightings might feasibly have been records of a single population.
The 8-part test (Vols A, B & C, pB.165) Background notes, states that babblers live in extended family parties, which are essential for both the co-operative feeding of young, and predator avoidance. For this section some better researched and more scientific evidence is presented by quotes of findings by Garnett and Crowley, 2000. It is pointed out that grey-crowned babbler is at threat from fragmentation of habitat, from which they gradually disappear due to smaller group size and reduced breeding success, less effective immigration and emigration and vaguely understood events that affect small populations. CE also quotes the scientific understanding that once a family group is lost from a fragment of previously secure habitat, natural re-colonisation is unlikely.
Although Greenloaning Biostudies noted the species around the Shannondale boundary during earlier studies, no conspicuous nests usually constructed by the species were seen, and additional target surveys have failed to locate the species. Yet CE has generally failed to consider this advice by Garnett and Crowley, and instead has found that the proposed fragmentation of the only known babbler group in the area is unlikely to have any impact.
By the many contradictory comments and findings by the SIS, it is quite clear that CE has no idea how to assess the proposed impacts by any components of the project on grey-crowned babbler. Clearly CE has no clue as to the needs of this highly vulnerable threatened species. Therefore it must be said that he was in no position to accept the degree of responsibility which, by the 8-part tests, is supposed to ensure the continued health and guardianship of the species within this local area.
The fact that prolonged studies across a broad range of suitable habitat, including the Chambigne Nature Reserve, has brought no sighting of other families of this very vocal and easily identified species should have sounded alarm bells.
As demonstrated by the attached paper, this Shannondale babbler population is quite possibly far from viable; is almost definitely not a part of a larger population, and is quite likely already on the brink of extinction.
Although not a hollow-dependent species, it could well be that the grey-crowned babbler's survival in nature could depend on retention of hollow-bearing trees, stags and maturing replacement trees. Until this possibility can be thoroughly researched and understood, and with removal of dead trees, dead wood and logs a recognised key threatening process for these birds, the planned removal of 74 old stags; 112 maturing habitat trees, and 25 old growth habitat trees by the access road is totally unacceptable.
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Patricia Edwards, Scientific Licence No No S11209