Luke Flanagan (Roscommon-South Leitrim, Independent)
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26. To ask the Minister for Arts, Heritage and the Gaeltacht the rates of growth of active raised bog habitats in special areas of conservation; and if he will make a statement on the matter. [10730/14]

Jimmy Deenihan (Kerry North-West Limerick, Fine Gael)
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Active raised bogs are acid, peat forming, rainfall fed bogs, with a water level generally higher than in the surrounding areas and dominated by bog mosses (Sphagnum species) which are the main peat forming species. The principal peat forming bog mosses require water tables over, at or slightly below the bog surface for most of the year and water levels rarely drop more than 20cms below the bog surface even during dry summer weather. These acid and permanently wet conditions minimise decomposition of the biomass produced by the plants each year. This in turn leads to the accumulation of the partially decomposed plant material known as peat. Peat accumulation proceeds slowly at an average rate of only 1-2mm/year or approximately 1 metre every 1,000 years. This habitat now occupies just over 1,210ha in the Special Areas of Conservation (SACs), down from an estimated 1,940 in 1994 and over 99% less than the area it once occupied in Ireland. Even in the raised bog SACs, the active bog habitat now only covers less than 12% of the remaining high bog area whereas, in intact bogs, it would occupy almost 100%.

This habitat is very sensitive to any changes in water levels caused by the installation of drains, by increases in horizontal runoff rates due to increased surface slopes, or changes in directions of surface flows. Water levels can also be affected by increased vertical losses due to development of cracks or swallow holes or increased hydraulic gradients between the surface and base of the bog. Both drainage and turf cutting can cause such adverse hydrological changes with consequent widespread ecological impacts. These adverse changes cannot be reversed unless the hydrology of the area becomes suitable once more for peat growth. Unfortunately some of the changes arising from drainage and turf cutting are irreversible and can greatly reduce the potential for restoration to active bog habitat. Severe fires can also damage the vegetation and surface peat layers of the bog and temporarily halt peat growth even in actively growing bogs. Fires can also speed up the drying out process if it is already underway and dried out bogs are much more susceptible to further fire damage.

The area of active raised bog at a national level has been assessed as Unfavourable Bad-Decreasing - the lowest possible ranking under the Habitats Directive assessment system. Its extent has decreased in both reporting periods up to 2013 and 2007. These assessments were based on changes in the area of active raised bog mapped during the baseline survey in 1994-5 and two monitoring surveys in 2004-5 and 2011-13. In both monitoring periods almost all bogs surveyed were within the SACs and therefore the results are representative of the condition of the raised bogs in the SAC network. The basic mapping methods were similar for all 3 surveys but the availability and use of GPS microcomputers, in the field, has undoubtedly improved the accuracy of the mapping in the 2007 and 2013 reporting periods. When comparing results from the different surveys, efforts are made to ensure consistency of interpretation between the different survey dates.

The results of the most recent monitoring survey in 2011-13 showed a slight decrease of approx. 1.5% in the area of active raised bog when compared to the results of the 20004-5 monitoring survey. This loss is substantially smaller than the 25% - 36.8% decrease shown when the results of the 20004-5 monitoring survey are compared with the results of the baseline survey in 1994-5. In addition, comparison of 1990s and 2004/05 vegetation descriptions indicated that there were significant declines in habitat quality as the wettest vegetation types in the active bog habitat were much more severely impacted. Comparisons of rates of loss between sites identified a strong relationship between habitat losses and the location and intensity of major impacting activities such as turf cutting.

The slow-down in the rates of loss of Active Raised Bog are considered to be due to a combination of factors. These include acquisition of turbary rights by my Department, the implementation of peat cutting cessation schemes which resulted in a substantial decline in peat cutting rates overall and a complete cessation in some sites, the fact that practically no new drainage took place on the high bog in the new reporting period (2007-2012) and the positive effects of restoration works undertaken with many sites developing new active peat forming areas. The adverse effects of extensive drainage works undertaken in the 1980s and early 1990s period would have continued to cause major habitat losses in the 1994/95-2004/05 period.

However, this rate of loss would be expected to decrease over time as all the more vulnerable areas were impacted initially. In addition, the natural blockage of drains by slumping and Sphagnum growth would have further reduced the drainage impact and therefore the rate of loss. It is estimated that there was 51ha of active raised bog lost during this period but that this was offset by the successful restoration of 38 ha of active bog on 12 bogs leaving a net loss of 13ha. In addition, the restoration works on those bogs and on another 9 SACs would have slowed the rate of loss of active bog and improved the condition of the non-active bog habitat. It takes at least a decade for restoration works to restore significant areas of active bog.

It is hoped that, in the next Habitat Directive reporting period (2019), a stabilisation in the area of active bog can be reported but that will depend on our ability to prevent further damaging impacts and, with community support, implement a program of restoration works. If we can do that we can look forward to significant increase in active bog at the following reporting period in 2025.