Detailed Flora, Vegetation and Targeted Survey
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Learmonth Pipeline Fabrication Facility Detailed Flora, Vegetation and Targeted Survey Prepared for: Subsea 7 November 2018 Submitted to Client Document Prepared Reviewed Admin Revision Reference by by Review Copies Date 2755AB A DRAFT SF, NW SW, TS NL 1 Electronic (email) 14/09/18 2755AD C CLIENT FINAL SF HT SH 1 Electronic (email) 01/10/18 2755AD D CLIENT FINAL SF,HT SW SH 1 Electronic (email) 13/11/18 Disclaimer This report is issued in accordance with, and is subject to, the terms of the contract between the Client and 360 Environmental Pty Ltd, including, without limitation, the agreed scope of the report. To the extent permitted by law, 360 Environmental Pty Ltd shall not be liable in contract, tort (including, without limitation, negligence) or otherwise for any use of, or reliance on, parts of this report without taking into account the report in its entirety and all previous and subsequent reports. 360 Environmental Pty Ltd considers the contents of this report to be current as at the date it was produced. This report, including each opinion, conclusion and recommendation it contains, should be considered in the context of the report as a whole. The opinions, conclusions and recommendations in this report are limited by its agreed scope. More extensive, or different, investigation, sampling and testing may have produced different results and therefore different opinions, conclusions and recommendations. Subject to the terms of the contract between the Client and 360 Environmental Pty Ltd, copying, reproducing, disclosing or disseminating parts of this report is prohibited (except to the extent required by law) unless the report is produced in its entirety including this cover page, without the prior written consent of 360 Environmental Pty Ltd. © Copyright 2018 360 Environmental Pty Ltd ACN 109 499 041 360 Environmental Pty Ltd 2755AD Detailed Flora, Vegetation and Targeted Survey Learmonth Pipeline Fabrication Facility Subsea 7 Abbreviations ABBREVIATION DEFINITION 360 Environmental 360 Environmental Pty Ltd BAM Act Biodiversity and Agriculture Management Act 2007 (state) BoM Bureau of Meteorology DAFWA Department of Agriculture and Food Western Australia DBCA Department of Biodiversity, Conservation and Attractions (Formerly DPaW [Department of Parks and Wildlife]) (state) DEE Department of Environment and Energy EPA Environmental Protection Authority (state) EPBC Act Environment Protection and Biodiversity Conservation Act 1999 (Commonwealth) ESA Environmentally Sensitive Area ha Hectare IBRA Interim Biogeographic Regionalisation for Australia km Kilometres mm Millimetres MNES Matters of National Environmental Significance PEC Priority Ecological Community PMST Protected Matters Search Tool TEC Threatened Ecological Community TPFL Threatened and Priority Flora Database TP List Threatened and Priority Flora List WAH Western Australian Herbarium WAOL Western Australian Organism List WC Act Wildlife Conservation Act 1950 (state) WoNS Weeds of National Significance 360 Environmental Pty Ltd i 2755AD Detailed Flora, Vegetation and Targeted Survey Learmonth Pipeline Fabrication Facility Subsea 7 Executive Summary In support of the Learmonth Pipeline Fabrication Facility (Learmonth Facility), Subsea 7 commissioned 360 Environmental Pty Ltd to undertake a series of Flora and Vegetation Surveys at the site, which is located approximately 35 km south of Exmouth, Western Australia (the Survey Area). The Flora and Vegetation Assessment was completed over three field surveys. From these, a total of 126 flora species, representing 87 genera and 32 families were identified in the Survey Area. The most commonly occurring families were Fabaceae (24 taxa), Chenopodiaceae (10 taxa) and Poaceae (10 taxa). The most frequently recorded genus was Acacia. No Threatened flora were recorded during the field survey. One Priority flora, Corchorus congener (P3) was recorded in abundance across the wider Survey Area including within the Project Envelope. Based on the desktop study, other than C. congener, no other priority flora are considered likely to occur. One potentially new species, Calytrix sp., was recorded in the wider Survey Area and was vouchered at the WA Herbarium for further study. It is likely to receive a phrase name and Priority status in the future. Calytrix sp. only occurred at one location and does not occur in the Project Envelope. Ten vegetation types were described and mapped during the survey. The vegetation types recorded during the survey are considered typical of the Carnarvon bioregion. The most common vegetation type was AgTe, which makes up 37.9 % of the Survey Area. The results from the DBCA Threatened and Priority Ecological Community Database did not identify any TECs or PECs occurring within a 50 km radius of the Project Envelope. Based on a combination of the database searches, desktop study and comparison of vegetation present in the Survey Area with descriptions of known TECs and PECs of the Pilbara Region (DBCA region boundaries) none of the vegetation types recorded during the survey are considered to represent a TEC or PEC. Vegetation condition ranged from Very Good to Completely Degraded. The majority of the Survey Area is considered to be in Very Good condition (82%). Weed diversity was considered low with eight weed species recorded, none of which represent a Declared weed or Weed of National Significance. Abundance of *Cenchrus ciliaris was high across much of the Survey Area, particularly within the drainage lines and along tracks. Other disturbances in the Survey Area includes heavy grazing and trampling by sheep, vehicle tracks and litter. 360 Environmental Pty Ltd ii 2755AD Detailed Flora and Vegetation Assessment, and Targeted Survey Learmonth Pipeline Fabrication Facility Subsea 7 Table of Contents 1 Introduction .................................................................................................. 1 1.1 Background ............................................................................................................ 1 1.2 Objectives and Scope ............................................................................................ 1 2 Environmental Context ................................................................................. 4 2.1 Biophysical Environment ........................................................................................ 4 2.2 Biological Environment ........................................................................................... 5 3 Methods ....................................................................................................... 9 3.1 Desktop Study ....................................................................................................... 9 3.2 Field Surveys ........................................................................................................ 11 4 Results ........................................................................................................15 4.1 Limitations and Constraints ................................................................................. 15 4.2 Desktop Study ..................................................................................................... 17 4.3 Field Survey ......................................................................................................... 19 5 Discussion ...................................................................................................35 5.1 Flora ..................................................................................................................... 35 5.2 Vegetation ............................................................................................................ 36 5.3 ESAs .................................................................................................................... 37 5.4 Regional Representation ...................................................................................... 37 6 Limitations ...................................................................................................38 7 References ..................................................................................................39 List of Tables Table 1: Land Systems within the Survey Area ................................................................. 6 Table 2: Pre-European Vegetation Types within the State and Regional Representation (Government of Western Australia, 2018a) .......................................................... 7 Table 3: Database Search Particulars ............................................................................... 9 Table 4: Limitations and Constraints Associated with the Survey Area.......................... 15 Table 5: Range Extensions of Species Recorded within the Survey Area ....................... 26 Table 6: Introduced Flora Recorded in the Survey Area .................................................. 31 Table 7: Vegetation Type Descriptions and Extent in the Survey Area. .......................... 32 Table 8: Percentage Similarity of Sites within the Survey Area ...................................... 33 Table 9: Vegetation Condition Extent in the Survey Area ............................................... 34 360 Environmental Pty Ltd i 2755AD Detailed Flora and Vegetation Assessment, and Targeted Survey Learmonth Pipeline Fabrication Facility Subsea 7 List of Figures Figure 1: Location of the Survey Area............................................................................... 3 Figure 2: Monthly Rainfall,