FIELD TECHNIQUES IN BIRD STUDIES COURSE EYRE BIRD OBSERVATORY NOVEMBER 2016 REPORT AND SUMMARY OF RESULTS

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1 FIELD TECHNIQUES IN BIRD STUDIES COURSE EYRE BIRD OBSERVATORY NOVEMBER 2016 REPORT AND SUMMARY OF RESULTS The Field Techniques in Bird Studies course has been running for many years at Eyre Bird Observatory and always attracts an enthusiastic group of fledgling ornithologists keen to develop their birding skills. The 2016 brood was no different. Course leaders Tegan Douglas and Kelly Rayner were joined by Aaron Goldfinch, Alan Bewsher, Brooke Richardson, Caleb Newton, Heidi Nore, Merryn Pryor, and Natasha Brown. Two of these students were supported by generous grants from BirdLife WA. The weather was near perfect and there was abundant flora and fauna activity to liven up the observatory. The first morning of the course was spent mist netting around the observatory, with nets set up near the Rope Walk and by the Beach Track. This gave everyone some close contact with the birds they would be encountering for the rest of the week, as well as familiarising everyone with the lay of the land. We banded 75 birds of 8 species, including 8 Singing, 7 Brown and 50 New Holland Honeyeaters, 1 Spotted Pardalote, 1 White browed Babbler, 2 Grey Shrike thrush, 2 Silvereyes. Three Welcome Swallow nestlings, from a single nest in the shed, were also banded. Amongst the adult birds banded were a number of retrapped birds, carrying bands from previous mistnetting activities. While most of these were from the banding efforts of Wendy and Alan Pilkington during their caretaking stint in 2015, some older retraps were also caught, including a 5 year old Grey Shrike thrush, and 3, 4 and 6 year old New Holland Honeyeaters. The wader count along Kanidal Beach recorded six transcontinental migrants, including Rednecked Stint (10), Sanderling (4), Ruddy Turnstone (4), Grey Plover (1), Lesser Sand Plover (1) and the Common Greenshank (1), on the beach. Of the more resident birds we recorded Red capped Plovers (64), Pied Oystercatchers (14) Caspian Tern (1), Pacific (4) and Silver (45) Gulls, Australian Pelican (5), Pied Cormorant (7). Other beach visitors included Emu (2), Nankeen Kestrel (2), White fronted Chat (2), Willie Wagtail (2), Australian Raven (7) Welcome Swallows (4), Dusky Woodswallows (2) and Australian Pipit (4). A beachwashed Fairy Penguin, Green Turtle and a Sheep (!), as well as what proved later to be a Soft Plumaged Petrel, added extra interest to the trip. Eagle eyed spotting later in the week by Natasha added another bird to the beach list a Red necked Avocet! The presence of so many waders allowed the students to conduct a behavioural key to the waders of Eyre. Waders can be difficult for the novice to identify on appearance alone, so constructing a behavioural key allowed participants to exercise their powers of observation to focus on how birds feed, use their habitat and interact with other birds. While obviously not exhaustive, as it can only be constructed from the species recorded and behaviours seen at the time, it still provides an additional strategy for bird identification. This key is presented below. In addition to bird identification exercises, we undertook several exercises to measure bird density and abundance around the observatory. These exercises have been conducted every

2 year on this course, so compiling the results over the years gives us a long term picture of the changes in bird numbers around the observatory. We use several different methods, with point counts providing good data for mobile birds, and territory mapping giving good figures for resident, territorial species. Standardised survey techniques such as ABC surveys allow for comparisons between site, and account for survey effort. Comparisons between the counting methods usually show some agreement in trends, but comparing the results from the same method from previous years is best to get an idea of trends for individual species. Results of abundance data collected during the course have been published previously in Corella (2010) 34:1 6. Table 1: Results of Australian Bird Counts at Eyre Bird Observatory in 2016, expressed as birds per hectare. ABC Survey Area Standard Rehab Total size of area searched 6 ha 4 ha Nankeen Kestrel Brush Bronzewing Rainbow Bee eater Blue breasted Fairy wren Spotted Pardalote White browed Scrubwren Weebill Spiny cheeked Honeyeater Singing Honeyeater White eared Honeyeater New Holland Honeyeater Brown Honeyeater White browed Babbler Grey Shrike thrush Golden Whistler Willie Wagtail Grey Butcherbird Australian Raven Welcome Swallow Silvereye Here is a summary of the results of the various counts that we made at Eyre in Australian Bird Counts (20 minute, 2 hectare area searches) were made in five areas three areas of well established vegetation around the observatory and two recently rehabilitated areas on the dunes towards the beach (Table 1). While bird diversity in the wellestablished vegetation was higher, some interesting comparisons showed up. While some species (Brown Honeyeater, Grey Shrike thrush, Willie Wagtail) were found in equal proportions in the two habitats, some potentially favoured one over the other. Where New Holland Honeyeaters were recorded at a higher density in the remnant vegetation, Blue breasted Fairy wrens, Singing Honeyeater, and Silvereye were recorded at higher densities in the younger vegetation. The White browed Babbler was the only bird recorded in the rehabilitated vegetation that wasn t also recorded in the older vegetation.

3 Table 2: Density of birds (birds/ha) determined by Point Count along the West Track in November 2016, with comparative data from earlier years. Denotes where birds were not present in great enough numbers to run the analysis. Density (birds per ha) Year Species Brush Bronzewing Fan tailed Cuckoo 0.21 Blue breasted Fairy wren 2.55 Spotted Pardalote Striated Pardalote 0.64 Inland Thornbill White browed Scrubwren Weebill Singing Honeyeater White eared Honeyeater 7.32 Brown Honeyeater New Holland Honeyeater Red Wattlebird Grey Shrike thrush Grey Currawong Australian Raven Silvereye Table 3: Bird densities determined by territory mapping a 22.5ha grid around the observatory. Densities are shown as birds per hectare, and denotes where birds were not present, or density was unable to be determined. Density (birds per ha) Year Species Blue breasted Fairy Wren Spotted Pardalote Striated Pardalote 0.49 Inland Thornbill White browed Scrubwren Weebill Red Wattlebird 0.58 White eared Honeyeater 0.18 Brown headed Honeyeater Dusky Woodswallow 0.31 White browed Babbler White winged Triller 0.09 Golden Whistler Grey Shrike thrush Grey Butcherbird Grey Currawong Willie Wagtail For the Point Counts along the West Track we calculated (by graphing and calculation) the densities of seventeen species. Comparing the figures with the previous years (Table 2), you can see some changes in them. For mapping around the observatory we obtained densities for seventeen species (Table 3). The densities from Point Counts are more realistic for nonterritorial birds than the mapping figures. However, both methods show a general absence of Striated Pardalotes during the course over previous years, as well as a decline in Spotted Pardalotes. Point counts show number of Silvereyes remain high, and territory mapping suggests consist numbers of Inland Thornbills over the last three years. In addition to our bird related activities, we recorded eight species of reptiles. From the pitfall traps we recorded Common Scaly foot (Pygopus lepidopodus); Marble faced Delma (Delma australis); Spotted Military Dragon (Ctenophorus maculatus); and (Ctenotus euclae). Opportunistic sightings included the Heath Monitor (Varanus rosenbergi); Common Thicktailed Gecko (Underwoodisaurus milli); Dugite (Pseudonaja affinis); and Southern Death Adder (Acathophis antricticus). While a thorough survey of the pygmy possum nest boxes yielded numerous spiders and cockroaches, only one of the boxes contained pygmy possums. To the delight of all it contained four crèched young, fully furred, but with eyes barely open. They managed to steal the spotlight away from the birds for quite some time. The week flew past, with days of new sightings and new accomplishments. The trip was made an absolute breeze due to the boundless enthusiasm of the course participants, and the delightful hospitality of our caretakers and hosts, Judy and Phillip Brace.

4 The 2017 Field Techniques in Bird Studies course is scheduled for 26 th November 2 nd December Please contact Tegan at tegan.douglas@birdlife.org.au for details. Tegan Douglas and Kelly Rayner, January Behavioural key to the waders of Eyre, November a) Observed in a group b) Only solitary individuals seen. Grey Plover 2.a) Only seen in single species groups b) Seen in mixed species groups a) Individuals moved in a tight group. 3.b) Individuals moved in a looser group/independently. Ruddy Turnstone Pied Oystercatcher 4.a) Movement appeared sedate, never frantic. Lesser Sand Plover 4.b) Movement was frantic, often constant a) Head bobbed frequently Red capped Plover 5.b) No head bobbing observed 6. 6.a) Foraged with bill at 45 angle. 6.b) Foraged with bill at 90 angle. Sanderling Red necked Stint

5 (back row left to right): Caleb, Aaron, Merryn. (front row left to right): Natasha, Heidi, Brooke, Kelly, Alan. (left to right): Alan, Natasha, Merryn and Caleb.