Pie

As many of you know, we have been recording the fish caught by the Dyfi ospreys for several years now.

One very elegant method of presenting data that compares the different species caught is via a pie chart. It also gives us an added joke opportunity of course - Monty’s fish pies. A pie chart is easy to understand and gives a simple breakdown of fish caught over a specific period.

We also record lots of other data to do with the fish caught and present these every Sunday evening on our Facebook page. But we actually do much more than this.

Over the last five weeks, we've had a study-placement student with us from Chester University. Elen has been studying the data we have collected over the last few years, and she has come up with quite a revelation (although we have theorised this for years!):

“There is no scientifically significant correlation between the fish species Monty catches and the Dyfi River intertidal zone”.

What does this mean?  Well, there is no overall tendency to catch flounders at low tide for example, or mullet at high tide - it is completely random. Monty seems to catch fish when he is (or any member of his family are) hungry. The species he catches have no association with the tidal height at the time.

Elen’s study confirms what we have been thinking for years. Monty is not restricted to tidal zones to catch his prey - a pivotal reason why ospreys breeding on estuaries do so well.

As we get more data and over many years, there is a lot more scientific research we can do, especially temporal studies - those spanning many years. It will be great to see how the various fish stats compare over time and to see any underlying trends.

Thanks to Vicky and Alwyn for all the fish stats every week, and of course Elen for her research. Diolch.

Eggs

We saw something quite unusual on Friday night. Monty incubated the two eggs for the whole night shift. From 22:43 to 05:50 to be exact. It is usually the female that incubates during the night.

We’ve seen Monty do this before and it has been recorded at other nests, but it is quite rare nonetheless.

Monty on egg “watch” - dreaming of lawn mowers

As I write, today is DAY 30 since the first egg was laid. The incubation range for ospreys is somewhere between 35 - 42 days, so not long to go now.

Here’s Monty shuffling the eggs around - in daylight this time. Egg No 1 on the right (the paler of the two) and Egg No 2 on the left.

A massive thanks to all of our 24hr protection volunteers - not long to go now before we can put the matches away for another year. Looks like you’ve managed to keep more awake than Monty has recently.

Chips

We get asked this question a lot at this time of year... “How do you know it’s another osprey that is intruding - why not a kite, a fox, or a person for example?”

Well, it’s quite simple. Here’s the secret, so don’t tell anyone...

Ospreys make a very characteristic ‘chipping’ kind of sound when other ospreys come too close to the nest. Have a listen to Glesni this week when Blue 24 (yes, she’s still around!) was eyeing Monty’s mullet that he was eating on a perch on Cors Dyfi reserve. These ‘chips' continue until Blue 24 retreats to a safer distance when she no longer poses a threat.

Ospreys only react like this to conspecifics - other ospreys. Alarm calls to all other species, including humans, are quite different.  

Monty tucks in to a mullet whilst Blue 24 looks on from a nearby electricity pole

Now I bet you never thought you’d see the day when you read a blog about Pie, Egg & Chips on an osprey website?

(And to all our American friends, chips in the UK are fries, crisps are chips and tomatoes are tomatoes. Simples!)