I am not sure the blog is the problem, if I search with a query containing the title of that article: https://www.google.it/webhp?q=antarctica+photography+safari
I can find it as third result. Which keywords are you after? Because if I narrow the search to just antartica+photography things change.
If I look at the keyword density in that article (like just using this tootl http://tools.seobook.com/general/keyword-density/), I get the impression without going black hat or irritate google copy could be a little bit more keyword focused.
The body is 900 words which is not so bad. But if I query for antarctica+photography competitors have a much larger copy and a probably better structure (headings are not just dates but do feed keywords to crawler).
Have you run a report on semrush for the domain? http://imgur.com/1pJ3G1i 229 positions is not much. Expecially given the 243 backlinks, which is not bad either: http://imgur.com/cuIwiLa
I would try to improve the copy of the articles, check the html in more depth, and review the backlinks profile for all the usual things (link quality, anchor diversity, deep linking, etc..).