Friday, 31 March 2017

March - Recent Sightings

March started with a real bang! While working on the front of the dunes a Long-eared Owl flew from the edge of the Pinewoods. The good luck continued with sightings of Pallid Harrier over the reserve and the Holkham area.

The reserve in all its glory

With the heavy rain, the wildfowl gravitated up the scrapes with 10,756 Wigeon enjoying the shallows along with 349 Teal, 208 Mallard, 270 Shoveler and 297 Gadwall. The Tufted Duck and Goldeneye preferred the ditches. Only 600 Pinkfeet were counted the majority already migrating north to their nesting grounds in Iceland and Greenland.

Waders such as Dunlin, Lapwing, Snipe, Curlew, Redshank, Golden Plover and the first Avocets have been coming and going. While there have been no sightings of Bitterns I heard their first growls along with plenty of squealing Water Rails.

Herons have been seen returning back to the Heronry

Birds of prey have been magnificent. 13 Marsh Harriers gathered on the reserve as well as Buzzard, Peregrine, Kestrel and Red Kites. The Norton Barn Owl is still a regular sight in the early mornings.

A Marsh Harrier checking out a possible nesting site.

Smaller birds have included Water Pipit, White Wagtail, Reed Bunting were seen as well as my first Treecreeper on the edge of the Pinewoods.

Our first invertebrates have been seen on the reserve with a surprise Buff-tailed and Early Bumble Bee flying past and a Small Tortoiseshell and Comma making an appearance.

There have also been a few fresh Peacock Butterfly about.

To top things off 3 Cranes were seen flying over the reserve on two consecutive weekends. 

PS While writing this a little Field Vole made an appearance, creeping through the open door and hiding behind my wellies! 

Monday, 20 March 2017

Why Birds?

Without the commotion of summer and with the promise of the survey season around the corner spring is one of my favourite seasons. Waders such as Lapwing and Redshank are migrating back to Holkham to nest; Spoonbills have been spotted; Pink-Feet have departed for Greenland and the warden team are preparing for the breeding bird survey season to start. But why do we and most other reserves concentrate so much time on monitoring birds? Why not mammals or insects?

Our early morning geese counts are nationally important.

To tell the truth, we don’t. At Holkham, we monitor a range of species such as Natterjack Toad,  Water Vole,  moths and a range of plants. We even have one of the longest running butterfly transects in the country.

However, birds are the relatively easy to monitor. Birds are conspicuous, meaning they are easy to identify and count. Mammals, on the other hand, are elusive and some groups of insects are difficult to identify without specialist knowledge and equipment.  Birds are also a great indicator species that respond to the health of the entire habitat and respond to changes in predictable ways.

Holkham is an important site for breeding waders. 

The link between bird species and their habitats make them key for identifying habitat quality. Waders at Holkham feed on important mud-dwelling invertebrates which depend on a delicate balance of mud, water and nutrients. Should the numbers of birds change it could indicate a shift in the habitat. The biodiversity of bird species can also indicate successful wider conservation efforts. A study of bird and butterfly species showed that the two were correlated which suggested that the number of bird species would also indicate the diversity of butterflies in small patches of habitat1. Another study showed the spices richness of birds correlated with six other taxonomic groups2.This shows that monitoring bird diversity can give a clear indication of overall biodiversity.

During the summer we map the calls of song birds in the pine woods.

Birds are incredibly useful as indicators for conservation as well as a familiar, fascinating and colourful creature.

  1. Blair, R.B., Birds and butterflies along an urban gradient: surrogate taxa for assessing biodiversity? Ecological applications, 1999. 9(1): p. 164-170.
  2. Kati, V., et al., Testing the value of six taxonomic groups as biodiversity indicators at a local scale. Conservation biology, 2004. 18(3): p. 667-675.