tackling invasive animals - bill handke
DESCRIPTION
The Canberra Indian Myna Case Study - Presenter: Bill Handke, Canberra Indian Myna Action Group Inc Abstract. Biosecurity and mathematics go hand in hand. The numbers count when assessing the biosecurity impact of an invasive species - that determines in part whether there is a threat. And the numbers help to determine the appropriate response strategy at different stages of the incursion. This is well demonstrated by the experience with the Indian (Common) Myna bird. The Canberra Indian Myna community-action control program is a case where the science, mathematics and community environmentalism come together to provide a bio-security win. The Indian (Common) Myna bird is international recognised as a major invasive species, with serious environmental, economic (horticultural and viticultural) and human health risks, and for being an amenity nuisance. This bird, introduced into Melbourne in the 1860s – to remove insects in Melbourne’s market gardens - and subsequently taken to Sydney and Cairns in the 1880s, is now a common pest along the eastern seaboard (from Far North Qld to Melbourne) and extending inland to mid-west Qld and New South Wales through to Bendigo. Only introduced to Canberra in the 1960s, the Indian Myna by 2006 had become the 3rd most abundant bird in suburban Canberra (Canberra Ornithologists Group [COG] 2005-06 Garden Bird Survey [GBS]). At that time, in every week of the year, the average maximum number of mynas observed by the COG surveyors within a radius of 100 metres of their home was 4.96 birds. This was a population which in 40 years had grown to an estimated 93,000 – 150,000 birds. Numbers count as high numbers of mynas can have a significant impact on native wildlife, on horticultural crops, and on public amenity. Numbers count as increased populations of mynas lead to competition pressure for food and nesting sites, which triggers expansion in new areas. And the trapping and high “knock-down” numbers count. The Canberra community-action program has had a significant impact at the local level on myna numbers. Mynas are now the 20th most abundant bird in Canberra (Canberra Ornithologists Group [COG] 2011-12 Garden Bird Survey). With records of 45,800 mynas trapped, the average maximum number of mynas recorded every week in 2011-12 by the COG GBS observers were 1.38 birds. The change has been profound. The community reports that as mynas are removed the small birds are back in their gardens and rosellas are back nesting in tree hollows and nesting boxes. The lived experience tells us a lot, but it is good science based on good mathematics that confirm the fact: if we want to maintain our native biodiversity across our landscape, we need to tackle the bio-invasion threats.TRANSCRIPT
Tackling Invasive Animals
- numbers count !
The Canberra Indian Myna Case StudyBill Handke
Canberra Indian Myna Action Group Inc
Overview of Talk
• Incursion stages / response
• The Indian Myna– its incursion– the threat– international experience– our actions
• The Results
Invasives - Incursion Stages and
Management Response
Indian (Common) MynaSturnus tristis
• Native to Indian sub-continent– distinctive colouring and call
– aggressive / territorial • but roost communally
– opportunistic feeder : omnivorous
– long lived
– breeds Oct – March
adaptive, intelligent,
highly invasive
The Myna Invasion
• Introduced Melbourne 1862– to control locusts in market
gardens
• Taken to Qld canefields (1883)– to control cane beetle
• same as for cane toad
• Brought to Canberra in 1968
• Now across eastern seaboard
Indian Mynas in Canberra
• Introduced in 1968
• Est. at 250 per km2
• Across all suburbs and urban nature reserves
The Case Against #1
• Major threat to native wildlife
– out-compete native birds for nesting hollows
– feed on:• eggs, chicks, skinks etc & insects
– drive small birds out of gardens
– a particular threat to: • parrots
• endangered insects and lizards
• Degrade woodland ecosystems
– by reducing ecosystem services by other birds
Impact of mynas on abundance of cavity-breeding natives- research by Kate Grarock
Under threat
At Serious Risk
Golden Sun Moth
Synemon plana
Perunga Flightless Grasshopper Perunga ochracea
Grassland Earless Dragon
Coorooboorama Raspy
Cricket
Likely to also be affected
The International Experience
• Mynas have lead to the demise / decline of:
– Mangaia Kingfisher (Cook Is)
– Red-moustached Fruit Dove (French Polynesia)
– Seychelles Magpie Robin (Seychelles)
– Echo Parakeet (Mauritius)
– Tahiti Monarch (Tahiti)
– Long-billed reed warbler (Tahiti)
Why we are concerned # 2
• Human health risk– bird mites & blood-born parasites:
Ornithonyssus bursa & Dermanyssus gallinae • cause dermatitis, asthma, severe irritation and rashes
– problem from nests in roofs
– droppings: Ornithosis, Salmonellosis, Arboviruses, Plasmodia
• cause pneumonia, gastro– concern at outdoor cafes, factories, food warehouses
– potential vector for “bird flu”
Why we are concerned # 3
• Horticultural / agricultural pest
From Sakai et al. 2001
Kate Grarock’s nesting box
research
- impact of mynas on rosella breeding
From Sakai et al. 2001
Impact of mynas on Crimson Rosella breeding- nesting box research by Kate Grarock
High tree density
Medium tree density Low tree density
All tree density
From Sakai et al. 2001
Impact of mynas on Eastern Rosella breeding- nesting box research by Kate Grarock
Low tree densityMedium tree density
High tree densityAll tree density
CIMAG(Canberra Indian Myna Action Group Inc.)
Patron: Prof Tony Peacock
• Objective: – protect native wildlife from Indian Mynas
• & reduce myna nuisance in urban areas
• Strategy:– core elements
• raise public awareness• reduce their growth & spread• humane trapping program• support local govt / community-action groups• support scientific research on mynas
• Community-action approach– a successful model
• 1506 members / 1402 with traps
– now 38 programs in Aust
Myna characteristics…
• Sedentary - slow dispersal
• Commensal - associate with people
• Social – flocks and small groups
• Unpopular - noisy & messy
• Conspicuous – distinctive / in-your-face
+ Proven control techniques(trapping / baiting / netting)
…make them highly susceptible to strategic control
Tackling the problem — Actions # 1• Raising public understanding
– a threat to our wildlife, not just a backyard nuisance
• Reduce feeding opportunities– keep pet food inside– better waste control at schools, restaurants and shopping centres– stop direct feeding
• Reduce nesting opportunities– block up cavities in roofs– maintain vigilance on nesting boxes
• Reduce roosting sites– remove unsuitable shrubs / trees
• eg. dense exotic pencil pines, palm trees
• Plant suitable gardens– reduce open space (lawns) and plant native shrubs
Tackling the problem — Actions # 2
• Backyard trapping– positive local impact
– 46,200 mynas removed
– Protocol on Animal Welfare: with RSPCA
– Collaborative arrangement with RSPCA on disposal
• Supporting research– PhD projects
– euthanasing research
– Monitoring• Mynascan - Invasive Animals CRC
Keys to Community-action # 1
Approach based on public participation:
• build networks with impt orgs / prominent people– RSPCA, university, birdwatcher group, Govt, Landcare /
Catchment Management groups, gardening groups
• an aware and concerned public– program of public awareness raising
• media, high profile “champions”, public presentations, website, bulletins
– tap into public loathing of mynas
• sense of worth in activities / contribution– public to believe actions will make a difference
– need to see results
Keys to Community-action # 2
Large-scale participation needs:
• easy, practical and low-cost activities– complicated and costly obligations a turn-off
• simple, effective, easy-to-operate traps– members own and manage own trap– disposal method needs to be simple, but humane - quick,
painless & stress-free
• regular feedback to members
• continuous recruitment– recognise many members will “drop off”
• low administration load on organisation
Nesting targets
Traps
MynaMagnet
PeeGees
Myna-magic
(MiniMyna)
Are we having an impact?
The positive impact
• Consistent trapper reports:
– small birds back in people’s gardens
– rosellas / galahs back in nesting hollows & nesting boxes
– no mess / fouling in patios
– Peace !
– COG Garden Bird Survey results:
• myna numbers in Canberra have reduced
2011-2012 COG Garden Bird Survey Report
3rd most abundant Canberra bird in 2005-06
20th in 2011-12
3rd most common
20th most common
CIMAG starts
Trappers & Captures: as @ June 2006 – June 2013
The impact of trappingMt Taylor — Kambah side
Park gate Backyard 2km Circuit Walk 2 Mar 06 14 10 4110 Mar 12 10 3816 Mar 15 8 30
13 Apr 0 4 2023 Apr 0 6 2225 Apr 0 8 24
1 June 0 11 9 2 June 2 4 7 6 June 0 0 4
10 Aug 0 0 519 Aug 0 1 423 Aug 0 0 0
17 Sep 2 2 211 Oct 4 2 014 Oct 2 0 3
Indian Mynas removed
• Trapper success
0
10
20
30
40
50
60
70
80
% of successful trappers
1-10 11-20 21-50 51-100 100+
Jul-06
Aug
Sept
Oct
Nov
Dec
Jan-07Feb
Mar
Apr
May
Number of mynas caught in month
Myna / Starling ratio
0
500
1000
1500
2000
2500
PreJune
Aug Nov Feb May Aug Nov
Starlings
Mynas
“We can make a difference”
• Doing nothing = decline in native wildlife– needs a concerted, concentrated, co-ordinated &
sustained effort• at household, commercial and govt level
• Backyard trapping has positive local impact– but needs additional effort to have landscape impact
Thank you