Conditions were fortunately very good after a wild week of strong winds, rain and even a dusting of snow on the Wednesday. As a result of the snow many fern fronds have been crushed down and were providing an obstacle along the walking tracks. The temperature was relatively mild and although you could hear the wind in the tree-tops it was not that strong. First Light was predicted at 6:52 am and the official sunrise time was 7:21.
We had 38 volunteers which was more the enough to cover all 16 monitoring locations. After meeting at 6.15 am everyone was briefed and out into the field by 6:40. Kookaburras were the first birds to start calling and were very active and noisy for quite a while. It seemed like quite a long wait until we heard our first Lyrebird at 6:58 am. Most volunteers had vacated their sites by around 7:15 am and people started filing into the Guest House for breakfast by about 7:25.
The results were collated this year during Google Earth. The bottom of Lyrebird Ridge seemed to be quite active as well as the points around the suspension bridge and the Bulga Carpark. other sites were much quieter with only one or two calls heard.
Using our call triangulation method there ended up being a couple of anomalies with the results that made the certainty of the existence of a couple of birds 100% certain. (e.g 2 monitoring sites heard it calling but a closer one did not). Overall though we came up with a total of 9 birds calling for 2019 (which is one more than last year).
Another great turnout of 34 volunteers for this year’s survey, our annual Lyrebird Survey is by far our most popular activity and once again we were able to cover all 16 monitoring sites.
Weather conditions were quite good, at 5.30am heading up to Balook there was a substantial amount of moonlight with a clear sky and some cold air, At Balook however it was darker because of cloud cover blocking the moonlight and there was a slight breeze in the treetops.
Our full crew of volunteers arrived in good time and by 6.30am everyone had arrived and signed in and by 6.45am everyone had been briefed on their tasks and had headed out in the dark to their assigned monitoring stations.
Once in position there ended up being quite an unexpectedly long wait until Lyrebird calls were first heard, only a couple of locations recorded birds calling before 7am; which was when the majority of the sites started hearing birds, the latest any group had to wait to record any calls was 7.10am. Last year (2017) every site had birds calling by 6.55am.
The official sunrise time for Saturday June 2nd at Balook was 7.22am and first light was scheduled to appear at 6.52am which was almost identical to last year.
From our results we detected 8 birds calling in our search area, this figure was slightly down on recent years. It is hard to read too much into one years results but potentially the dry summer and autumn we have experience may be having an impact. Most birds appeared to be calling from forest areas with established Eucalyptus over-storey or rainforest. It would be great if some action can be taken to re-establish the original canopy species into areas of the park that have been degraded.
As usual we only count birds that are detected by at least 2 monitoring stations and some stations heard birds calling that were not in our survey area so are not included in the final tally.
Thanks again to AGL who generously supported the breakfast provided for the early rising volunteers.
Lyrebird Survey Results Summary Table 2010-2018
Number of Males Calling
(out of 16)
Windy making it hard to hear calls, especially in the more exposed sites.
Still and Calm
Wet, may have discouraged birds from calling. Several males sighted feeding but not calling.
We had a fantastic turnout of volunteers, which meant that all 16 sites could be covered with at least 2 volunteers at each site. (This is the first time we have covered all 16 sites since at least 2010).
Weather conditions were ideal (2nd year running) with little or no wind to muffle the sound of calls and it was not really all that cold!
Everyone got out to their respective positions in time; the earliest call was heard at 6.49am and by 6.55am every monitoring station had Lyrebirds calling.
The official sunrise time for Saturday Jun 3rd at Balook was 7.23am and first light was scheduled to appear at 6.53am. So, it seems Lyrebirds are fairly well tuned to begin calling at first light.
From our results, we detected 11 male birds calling, (not sure if it would be possibly with our method to detect two birds calling in close proximity to each other, but a couple of stations noted the possibility that they could possibly hear multiple birds calling from around the same direction.
Note: we only count birds that are detected by at least 2 monitoring stations.
This is our second highest number of birds recorded since at least 2010.
Thanks to AGL who helped to pay for the breakfast.
Don’t miss your chance to be involved with Friends of Tarra-Bulga National Park Annual Lyrebird Survey. This year it will be held on Saturday, June the 3rd. The meeting point for all volunteers is the park visitors centre at 6.15 am. The Survey takes only 30 minutes from the time the sun rises and the birds start calling, Straight after the count a free breakfast for all volunteers will be provided at the Lyrebird Cafe. To secure your place please email firstname.lastname@example.org or call David on 0488035314 by Wednesday 31/5/2017
In the pre-dawn darkness on Saturday the 18th of June, twenty-five volunteers and one Park Ranger were greeted with perfectly calm conditions for Tarra-Bulga National Park’s Annual Lyrebird Survey. Overnight showers had passed by leaving moist dripping foliage in their wake.
The survey is designed to monitor the density of Lyrebirds living in 60ha comprising of wet sclerophyll and cool temperate rainforest immediately to the east of the Tarra-Bulga National Park Visitors Centre. There are sixteen monitoring points strategically placed throughout the site and volunteers move to each site before adult male Lyrebirds start their morning calls at dawn. Volunteers then use a compass to record the direction and proximity of the Lyrebird calls. This year we had enough volunteers to cover all but one of the monitoring points.
Following the survey, lines representing the direction of the calls are plotted onto a map, and triangulation is used to establish the spots where birds were calling from. This year the results indicate we had at least nine (male) Lyrebirds calling in our 60ha zone. This corresponds to a density of one adult male Lyrebird per 6.7 ha. You can also assume that there will be female lyrebirds and immature males or non-calling males within our target area. To account for this to get our overall population of Lyrebirds we multiply the number of calling males by a factor of 2.5. It is believed that male Lyrebirds do not begin to breed until they are around 6 or 7 years old.
Summary of Tarra-Bulga National Park Lyrebird Surveys
The Annual Lyrebird Survey at Tarra-Bulga National Park has been carried out for the last 20 years as a means of detecting any changes of the population of the birds, within an area of the park covering from around the visitors centre area to the rainforest gully at the headwaters of Macks Ck. Although Lyrebirds are not considered endangered, they are at risk from natural disasters such as bushfires, habitat decline and attack from foxes, feral animals and domestic cats and dogs. The annual survey contributes to long term data on the density of the local population and helps park management plan their future management actions.
The Lyrebirds are counted not by attempting to spot them visually, but by listening out for their song. (Sometimes you may be lucky enough to see a bird but often they are out of sight perched in a tree canopy or in ferny understorey). The survey is undertaken during the Lyrebirds’ breeding season. At this time mature male Lyrebirds are all actively searching for females to mate with and it is during this time when they are reliably singing for much of the day. The survey is consistently undertaken at dawn (when the wind is often calmer and the Lyrebirds begin their morning calls, usually while perched up in a tree).
The count is carried out by distributing groups of volunteers across the survey area at
established monitoring points. Each of these points is marked with a numbered sign so that they can be found in the pre-dawn light. As the sun rises and the Lyrebirds start singing their varied repertoire, the volunteers use a compass to establish the direction the calls are coming from and estimate the distance (close, medium or far) that the call is coming from. The survey lasts for approximately 30 minutes, after which the volunteers generally go off and enjoy breakfast at the aptly named Lyrebird Cafe.
Once the survey is completed survey sheets are collected and the direction the calls were coming from are plotted as lines onto a map, where lines coming from several surrounding monitoring points meet, we can be confident that it is a location where a male Lyrebird was calling from.
We always cross our fingers and hope for favourable conditions on the morning of our annual Lyrebird Survey which this year was held on Saturday May 30th. This year there was no rain but unfortunately the wind was up and noisy gusts were swirling through the canopy.
The logistics of getting a large crew of volunteers up and ready to participate at 6.15am means that we can’t afford to be flexible with our dates so it is a matter of carry on regardless. This year we had 22 volunteers turn up for the count, with most people pairing up, we were able to cover 12 out of our 16 monitoring stations, as is often the case the 4 stations in the southern section of our count area were left out.
Volunteers did a great job of arriving by 6.15 and by the time instructions were given and stations allocated it was still a rush to get into position. I found that the sun was rising and some birds had started calling a few minutes before I made it to my monitoring point at 6.55am.
The next ½ hour was spent listening out for birds, at our site we could hear calling from three directions and once bearings were taken and noted we just settled in and enjoyed the surrounds. I noted some noisy Yellow-tailed Black Cockatoos moving in the canopy overhead as well as the odd loud crack from randomly scattered Eastern Whipbirds may potentially cause confusion for novice counters. Once our time was up we headed back along the track and soon came across a live sighting of a female Lyrebird (or perhaps a juvenile male?) wandering along the path.
Back at the guest house we once again had a great breakfast (thanks to Torben and Pam). After all the monitoring sheets were handed in it was time to analyse the results. The number of birds detected this year was down, although hopefully this is not cause for alarm; the survey relies on hearing the calls and the background noise of the wind makes them more difficult to detect. We definitely had 4 male birds calling in the survey area with one other likely one. Instances where it was noted that birds were calling very close to monitoring stations, helped to identify some of the Lyrebird locations with certainty.
A big thank you to everyone who made the effort to drag themselves out of bed so early and travel up to Balook to help out, your efforts to help conduct our annual surveys and monitor the local Lyrebird population is very much appreciated. Also thank you to our Ranger Craig who does a fantastic job setting up the monitoring stations and organising the troops. At the start of the count Craig pointed out that this was our 20th Annual Lyrebird Survey and that he had attended every one. Next year will be a big one (our 21st).
Clink on the link for a pdf map of the survey results.