Calling frogs

Spring is upon us. Male common frogs (Rana temporaria) have gathered in the pond at Pearson Park Wildlife Garden and call for females and scramble. There were plenty of males but I only saw two females in the pond and still no frogspawn. I have so many photos of the mating frogs from past years that today I decided to concentrate in trying to get the males in the moment they call. The male's white-bluish throats inflate and they tend to 'blink', which spoilt some of the photos, but I was quite pleased with a few. The call of the Common frog has been likened to a rumbling distant motorbike, but to me it sounds like a cat purring loudly, but in any case, it is only audible (to  humans anyway, I am not sure to females) within a range of a few meters, and sounds nothing like 'ribbet' at all!