This blog is about my journey to learn more about science, in particular, about some of the dynamics that apply to 2 marine snails in a small portion of the Great Southern Reef (see www.greatsouthernreef.com).
It is about growth, recruitment and mortality of the marine subtidal gastropods, Lunella torquata and Turbo militaris.
The project involves growth estimation from both tag-recapture data and length-frequency analyses. The length-frequency analyses also seem to indicate strong and weak recruitment years and the impacts of storms. Those aspects will feature in later posts.
I chose these two species for this project because they are:
- abundant along the east Australian temperate coastline (so good sample sizes are possible)
- easy to collect in shallow water (safe for my solo diving efforts with a modest compressor)
- commercially and recreationally taken, and a focus for indigenous harvesting (so someone is likely to be interested in my outputs)
- simple to tag with free, home-made tags and cheap, “super-glue” adhesive,
- robust enough to survive some handling, and
- the subject of some international and Australian research to build upon.
My aim in producing material that contains much more detail than a journal paper is to ensure some discipline – so the main target audience is me.
However, this represents a lot of work, reading and thinking so I would like to think it will also benefit at least one, or a few, other people. I suspect it might be helpful for budding scientists. My aim is to share my research journey, my data and my findings with:
- non-scientists who may be interested in the marine world
- late secondary and tertiary science students, who may be interested in the detailed nuts and bolts (including successes and mistakes) of a research project
- professional scientists interested in fish population dynamics and gastropod research.
This means the language will be too simple for some readers and possibly too technical for others. I apologise, in advance, to both.
My initial focus was growth, and logistically, I could manage half a dozen research sites to enable site, inter-annual, seasonal, and sex comparisons: complex enough to make the exercise interesting but not overwhelming. My main focus was Lunella torquata, but specimens of Turbo militaris have been tagged and recaptured (mostly opportunistically) along the way.
This gets me out on a boat in good weather; it is a good, safe physical activity (I am 70 years old); and it keeps my brain active, particularly in needing to learn programming in the R statistical environment. It is also connecting me with other, more competent, scientists. In fact, finding two new colleagues has already enabled a publication (Kienzle M, M Broadhurst and G Hamer, 2022. Bayesian estimates of turban snail (Lunella torquata) growth off south-eastern Australia. Fisheries Research 248, 106218.)
I see this project as an example of open citizen science. I don’t need the drama or pressure of a formal thesis, higher degree, or refereed publications, but I still want to produce and disseminate some good science. In my journey to this end, I am documenting and analysing my methods, anecdotes, data, hypotheses, tests and conclusions in this blog.
If it all has little legacy value, I will still have had some fun along the way and amused (bored) my wife and friends.
A self-published blog means each upload can contain more detail and explanation than in a formal manuscript. The information will be available much quicker than a long way down the track. Self-publishing also allows me a conversational style, more extensive exposition of issues, and incorporation of some old, unpublished data that has relevance to my thinking and approach. Finally, open science means making the raw data available which I am happy to do.
I have a draft list of about 35 posts, depending on how much I can fit in a post and how my skills change over time. If all goes well, I will aim at a post each month, but no doubt that will be variable.
As a teaser, I am including in this first post, a graph of tag-recapture data for all Lunella torquata recaptures that have been at liberty after tagging for more than 2 months. To anybody versed in regression, the high degree of variability is fairly obvious. This variability is why large sample sizes, careful analysis, and cautious conclusions are required.
