I have been contacted by Dr Andre Chiaradia, a marine biologist from Phillip Island Nature Park,  about 150 km east of Melbourne.  As you no doubt all know, we have a very popular tourist venue at Phillip Island whereby the tourist watch the fairy penguins come up the beach to their burrows each evening  soon after sunset.

Dr Chiaradia tells me that on the evening of 21 December last, there was a fog covering the beaches at Phillip Island, the consequences of which were that the penguins did not come in.  Talking to him on the phone, he says it is believed that the penguins navigate visually, so possibly they could not see the coastline.  I had a chat also with Lynda Chambers of BMRC who is also a bird-person and has published on penguin behavior.  She speculated that possibly the penguins were wary of coming ashore simply because conditions were different to normal... e.g.. the lights on the beach would have looked different under fog conditions... so caution/self-preservation could have kept them at sea due to the different appearance of the beach.

 Anyway, apparently the tourists sat there... no penguins came in... eventually the tourist went home, the fog lifted, and the penguins came in

 Dr Chiaradia has an automatic counter for the number of penguins crossing the beach; so on my web-page I have put a graph he sent me for the penguin counts that night and for normal conditions (viz the nights immediately before and after).

He wanted to learn a bit more about that fog, as he will write a short article for his group's "newsletter"... e.g how extensive the fog was.... what he would most like would be a satellite picture of the fog... so, if anyone can help him, he can be contacted at the above email address.
 

To use as a  brief background on the event, on my web page I have put links to the closest NASA MODIS visual image (for 0350 UTC 21 December), to that evening's Melbourne sounding 1100 UTC 21 December 2002 and the sounding for the preceding morning 2300 UTC 20 December.  I have also put up a few surface charts: 21 st December 00, 06, 12, 18

On the MODIS image, one can see that Phillip Island (at the southern tip of Western Port Bay) is under what looks like low-level stratus; though as we know surface observations gave this as fog.  Unfortunately the southern edge of the picture is quite close to Phillip island;but it looks like it (stratus) was fairly extensive going for several hundred kilometre; so if penguins do navigate visually, they could easily have been "lost".

 The synoptic situation looks like it was very weak northeasterly flow, with very little wind at all while the fog was on.  Around 12 UTC  a  prefrontal-trough front came in, bringing westerlies and clearing the fog.   The Melbourne soundings show a  strong low-level inversion; but the boundary layer is not particularly moist.   Perhaps the fog exerts out there can comment; but I would assume the fog is in warmer sea air advected in from the east... its hard to tell without a better satellite image.

The VRO guys out there forecast and observe fog all the time along this coastline; so no doubt they know the conditions under which it occurs.  It must be fairly rare at sunset as this was the first time Dr Chiradia knew of whereby the fog "rained on" the penguin parade ... any comments?

P.S.  Dr Chiaradia's email to me:

Hi John,

Nice to chat with you. This is the graph of number of penguins coming
ashore at night. I have plotted a day before and after the fog event. The
fog lift at 11:15pm. Only after that the penguins started to cross the
beach. This was very unusual. We know that penguins are strongly affected
by sunlight (they always come ashore after sunset and leave at dawn) and
moonlight (they usually depart earlier between full moon and last
quarter). So the decision of arrive and departure should be  guided by
light intensity. And we always have the suspicion that penguins use
landmarks for navigation. This fog event give support this theory, as the
arrival time was delayed by poor visibility. It would interesting to see
the extent of this fog.

If you have any information on this event, an image, etc... it will be
most appreciated.

Cheers  Andre