About Research 1
Why is research important for Brolgas, Sarus Cranes and their habitats? First in the Ozcranes Research Tour we look at ‘Scientific Method’ and ‘Abstracts’, with a quick note on ‘Citations’. Then read the abstract, or summary, for a scientific study by CD Littefield into why Greater Sandhill Crane numbers were falling in a US national wildlife refuge. The full article is also available online, it's interesting in itself, and it has parallels with breeding success issues for cranes in Australia.
In Research Tour Part 2», we look at peer review, ‘grey’ literature and links to current crane research in Australia and overseas.
..‘Anecdotal evidence’ or ‘Scientific method’
In 2005, as part of celebrating Einstein's key work published in 1905, a survey asked 250 renowned scientists: if you could teach the world just one thing, what would it be? ‘Scientific method’ was seen as a key contribution. It's partly defined as forming testable ideas and building experiments or studies to try and prove your idea wrong – to push it to the reasonable limit using methods that other, independent researchers can repeat to verify your work and extend it, and push knowedge ahead even further.
Reasoning is part of normal life: we observe some facts or events (‘anecdotal evidence’) and draw conclusions (‘induction’). Scientific method is what's needed to move on from a tentative conclusion (working hypothesis): a framework to test the boundaries. Were our observations good enough to support our working hypothesis, do they still apply if more variables are factored in, and in other places or times? Or were we tricked by, for example, a coincidence of timing?
..is placed immediately after the Title of a research article in a scientific journal. It's a concise statement of about 200 words on the work, its main findings, and its contribution to knowledge about the topic. Sometimes called ‘Summary’, and sometimes a list of keywords is added. The abstract and keywords are used by academic search engines (‘indexing databases’) to index the article.
Here's an Abstract from an article by Carroll D. Littlefield in the Wilson Bulletin, about Sandhill Crane breeding success in Oregon, titled ‘Demographics of a declining flock of Greater Sandhill Cranes in Oregon’.
Greater Sandhill Crane (Grus canadensis tubida) nesting success at Malheur National Wildlife Refuge, Harney County, Oregon, was 44% for 456 nests during 1966-1974, and increased to 54% for 640 additional nests during 1976-1989. Predators destroyed 241 (38%) clutches in the 1976-1989 period, with Common Ravens (Corvus corax) taking 63, raccoons (Procyon lotor) 43, coyotes (Canis latrans) 28, and unknown predators 107. Most clutches lost to unknown predators were likely destroyed by coyotes. A total of 52 clutches was either abandoned, flooded, or infertile. The mean annual number of fledged young from 1970-1989 was 31, and mean annual young mortality from hatching to fledging was 84.4%. Of young fledged, a total of 438 broods contained one young and 91 had two (x̄ = 1.14). The 6.7% mean annual recruitment at Malheur between 1970-1989 probably was responsible for a decline in breeding pairs, from 236 in 1975 to 168 in 1989.
Wilson Bulletin Vol. 107(4), 1995, pp. 667-674.
The Abstract (above) summarises Carroll D. Littlefield's research findings from one part of a long-term population monitoring study funded by the US Fish & Wildlife Service. After (large) numbers of cattle were removed from the breeding wetlands in the reserve, crane numbers rose. But later, monitoring picked up a decrease. Why?
← Sandhill Crane pair (Ian Montgomery)
This study showed significantly higher egg and chick survival in years when the reserve controlled predators. The conclusion was that due to so many nest failures, insufficient young were maturing to replace aging adults – a serious problem for long-lived birds like cranes – and predator controls were needed. Note, the mean annual recruitment rate of 6.7% is considered low, and a contributing or main factor in the decline in the number of breeding pairs. This is similar to the rate for Brolgas in southern Australia, presumed in part due to introduced foxes preying on chicks. It's also similar to the rate for Australian Sarus Cranes – the abstract is here» on Ozcranes, courtesy of the author Dr John Grant.
Check Carroll D. Littlefield's introduction (after the Abstract, full pdf) where he quotes (cites) earlier authors who established the baseline for his work. These are ‘citations’. Details of all previous authors he quotes to support points in his article, are listed at the end in ‘References cited’. This is important to help readers check his conclusions. After Littlefield's paper was published, later authors cited it in their own studies, and it is still quoted today. (Part 2 of the Tour includes a couple more points about citations).