We’re looking at detectability this week in Environmental Monitoring & Audit. Here are some relevant links:

1. First, check out Guru and Jose’s video explaining why detectability is important in species distribution models (there’s also some bloopers).

2. Then we have Georgia’s post about setting minimum survey effort requirements to detect a species at a site.

3. Another by Georgia about her trait-based model of detection.

4. And finally, a paper showing that Georgia’s time to detection model can efficiently estimate detectability.

And if you want more about detectability, check out a few posts of mine.

The diversity of science careers

Many different scientific career opportunities exist. Sometimes a “traditional” science career is portrayed as students travelling from undergrad, to postgrad, a post-doc research position or two, and then an academic position at a university.


First-person science career stories

Of course, such a career trajectory is atypical. Most scientists end up in other professions, branching out at various points from this academic path, and sometimes even veering back onto it. The variety of paths is almost as great as the variety of people on them.

It is not always easy to see examples of this diversity of career paths. That makes the website MySciCareer all the more useful. There you can read first-hand accounts of people who have followed various career paths in science.

So, if you are wondering about the options available in science, hop on over to MySciCareer, and browse around. You could even consider contributing a story.

How many surveys to demonstrate absence?

In the lecture today in Environmental Monitoring and Audit, I mentioned the model examining how much search effort is required to be sufficiently sure of the absence of a species at a site. This was based on a paper by Brendan Wintle et al. (2012).

You can read more about this topic here, with an attempt at an intuitive interpretation of the model, and some links to other examples where the prior probability (base rate) matters.

If you are particularly keen, you can read a copy of the manuscript here.


Wintle, B.A. Walshe, T.V., Parris, K.M., and McCarthy, M.A. (2012). Designing occupancy surveys and interpreting non-detection when observations are imperfect. Diversity and Distributions 18: 417-424.

DEPI Graduate Program

The Victorian Department of Environment and Primary Industries is recruiting for its 2014 Science Graduate Program. Details are available on its website:



Growling Grass Frog Metapopulations

Growling Grass Frog metamorph (photo: Geoff Heard)

The Growling Grass Frog (Litoria raniformis) is a great example of a species that can be modelled as a metapopulation. The dynamics of Growlers (as they seem to be known to those who study them) seem to be dominated by relatively frequent extinction and re-colonization of wetlands depending on their condition and arrangement.

Geoff Heard, who presented today’s lecture on metapopulations in Environmental Modelling, has been studying Growlers for years, particularly around Melbourne where they are threatened by urban development. You can learn a little more about them at Geoff’s website.

Population dynamics

Michael Bode has just covered population dynamics in Environmental Modelling. So it is excellent timing that we’ve just published a post by Brendan Wintle about population viability analysis on You can read it here, or a recent short synopsis on population viability analysis here by Hugh Possingham and me, which has just appeared in the Encyclopedia of Environmetrics.