The sun is shining and spring is well and truly here. Our marsh harriers (two males and four females) have been performing their sky dancing routines to impress each other for the breeding season. Keep your eyes peeled for them all around the reedbed.

The great crested grebes at Causeway Pool can be spotted weed dancing like they're in the Strictly Come Dancing final. They're so lovely to watch as they pass weeds and nesting material to one another. 

Most exciting of all is the boom of the bittern which can be heard in the mornings and evenings (and sometimes bits in the day too). If you stand on the Causeway by the 'Boom goes the bittern' interpretation panel (very handy), you can hear him in the reeds across the other side of the Causeway Pool at Island Mere. He is distant but his voice is loud and carries well. He often takes three breaths before a sequence of eight-nine booms. It is the strangest, most spectacular sound of spring at Leighton Moss. 

  Bittern by Ben Andrew (rspb-images.com)

The migrants are also rolling in. A huge flock of 200+ sand martins can be seen feeding on insects over the reedbed. You have to be quick to catch a photo as they zoom past but they are a joy to watch. Of an evening they are almost like a starling murmuration as they fly round en mass together, quite high above the reeds, catching insects. A sure sign of spring, we're hoping they will take an interest in the sand martin bank at Tim Jackson hide that we installed last year.

Our Visitor Operations Manager Kevin was lucky to have the mother otter and her cubs running towards him on the Causeway this week! Always a delight to see, keep an eye out for them on the Causeway and Lower Pools. 

Avocet numbers are now topping 50 so head to the Allen and Eric Morecambe hides to watch these elegant birds that are the emblem of the RSPB. You will likely discover a huge flock of black-tailed godwits there too - looking fabulous in their rusty-red summer outfits. 

With all of this and more to discover, new migrants like ospreys due in any day (and not forgetting it's Mother's Day, the perfect opportunity to treat your mum to a day wildlife watching and some cake in the cafe), we hope to see you soon!