Do the Strand?

The report (http://www.guardian.co.uk/environment/2008/jun/14/conservation.endangeredspecies) that a group of around 70 dolphins suddenly 'dashed' into a muddy location in Cornwall is intriguing. Around 26 of these animals died in spite of people attempting to help them back into the water. A range of explanations for such mass strandings have been offered. These include the possibility that these animals were panicked by nets (apparently unlikely in this case), the unusual Spring forcing the animals into shallow water in pursuit of small fish and the claim that the navy was exercising with a variety of 'secret' devices in the area (denied by the senior service). These events certainly are not uncommon and it is difficult to work out why particular occurrences happen.

Cockles of My Heart?

Here we go again! The local news is full of images of deaths of '6000 tonnes' of cockles in the Burry inlet (http://news.bbc.co.uk/1/hi/wales/south_west/7454536.stm) and about a possible petition to the National Assembly Government for a Public Inquiry. The current claims that the shellfish deaths might be related to 'a mystery bug' or to sewage from a water treatment plant are understandable but highly speculative. In relation to the second possibility, the Chairman of the Carmarthen River Festival has been quoted as saying "We want to know what's causing the cockles to die and how much sewage is going into the estuary". That statement inevitably links the deaths and sewage. Historically, however, the cockle numbers initially boomed in this location (possibly wiping out oyster and mussel stocks at that time) when the amount of human waste going into the river was high (before the development of the hi-tech £50m sewage treatment plant). The actual release of organic material into the river will have declined in recent times, meaning that there is less 'food' for these detritus feeders. The causes for the current problems are likely to be complex and could even involve (more speculation) the liberation of toxic heavy metals from river deposits (these highly coloured sands were generated as a result of smelting operations in the Industrial Revolution and subsequently buried over decades by river movements but changes in the river channel [its no longer controlled] could have made them more accessible). It's perhaps pertinent to note that I seem to remember declines in adult cockle numbers in years gone by being initially blamed on the voracious appetites of the Oyster catcher (a bird that was shot in large numbers). The crushing of cockle spat by 4-wheel drives and tractors used in 'harvesting' eventually appeared to be implicated in these local shortages. Cause and effect are never easy to establish in such cases.

Planet Thanet?

Decades after agricultural developments in places like the Netherlands, it has been announced (http://www.guardian.co.uk/environment/2008/jun/11/greenbuilding.food) that the UK is finally to have a major development involving hydroponically-grown plants in Thanet (Kent). The 'Thanet Earth' development will include 7 huge greenhouses (each 140m long and 8m high with its own rain water reservoir and power-generating station) on more than 90 hectares fine agricultural land. The crops (including tomatoes, cucumbers and peppers) will be suspended from the ceiling, so they can be tended and harvested at waist height. The plants will be 'rested' in the late afternoon but will be subjected to bright lights (workers will need sunglasses) from midnight onwards. The development (funded by a consortium of Dutch growers and the UK's largest fresh produce supplier) is intended to increase the 'UK's' crop of salad vegetables by 15% over most of the year (by providing 'perpetual summer'). Thanet Earth appears 'green' as it is planned to be independent of local water supplies for about half the year, to limit visual impact of light at night, to contribute power to the national grid and to push some of the carbon dioxide generated by burning gas into the greenhouses for the plants to use in photosynthesis. In another sense, however, these features are largely driven by economic considerations. The developers suggest that other sites in the UK suitable for such developments (in terms of sunlight as well as gas, electricity and transport links) are strictly limited and do not expect such activities to dramatically increase. The burgeoning increases in the costs of gas and water may further slow similar exercises. Although such developments might appear capable of generating food efficiently on a smaller acreage of land than traditional agriculture (perhaps giving scope for other land use), the economics suggest that they will not feed an endlessly increasing world population. The resources (in terms of what you have to put in) are still ultimately finite.

Seeing the Changes 107

Pale toadflax (Linaria repens) was blooming in Bynea along with Vervain (Verbena officinalis). A Seven-spot ladybird (Coccinella 7-punctata) had also emerged from its pupa. In Loughor, Meadow cranesbill (Geranium pratense), Wild privet (Ligustrum vulgare) and Mugwort (Artemisia vulgaris) were in flower.

Seeing the Changes 106

The first Field bindweed (Convolvulus arvensis) is in flower in Swansea. There is also a Buff ermine moth (Spilosoma luteum) in this location. In Bynea, the Common toadflax (Linaria vulgaris) is fully unfurled along with Greater plantain (Plantago major), Creeping thistle (Cirsium arvense) and Marsh bedstraw (Galium palustre).

It's a Different World!

Just returned from the Windsor area of Surrey. Where the rabbits (Oryctolagus cuniculus) don't run and Ring-necked parakeets (Psittacula krameri) argue in the tree tops (top and middle). Lots of Green alkanet (Pentaglottis sempervirens) and White bryony (Bryonia cretica) in the hedgerows along with yet another shield bug and Ladybird larvae.

Birder's Bonus 25

A pair of Lapwing (Vanellus vanellus) were operating around the Loughor estuary. These birds (or their relatives) were doing some impressive courtship aerobatics early in April.