Biodiversity Frequently Asked Questions

    

Q. Why should we worry about plants or animals that could
    escape into the wild?

• A. Historically our gardens have been landscaped by the introduction of many new plants from abroad. Some of these plants have come from as far away as Eastern Asia and Australia. Some people have bought new exotic animal species as pets and industries have brought in new species from abroad for commercial benefits. Many of these new arrivals to Northern Ireland pose no threat to our native biodiversity and are easily contained within our gardens, homes and industries.
  However, some of these introduced species escape into the countryside and become problematic as they thrive in our environment. Here they can out-compete our native species and even take over whole habitats, eventually altering them as they do well without the natural enemies that would limit their spread in their home countries.
  These species are known as ‘Non-native invasive species’ or ‘Invasive Alien Species’ and are now widely recognised as our second biggest threat to biodiversity loss, second only to that of habitat destruction.
  In some situations they can even lead to significant associated economic costs by damaging building foundations, clogging up our lakes and rivers or causing populations of commercially exploited native species to decline. Unfortunately, once established in the wild, these species are often very difficult and costly to control.

Q. What threat does the Non-native Grey Squirrel pose to our Native Red Squirrel?

• A. The grey squirrel originated from North America. It was believed to have been first introduced into Ireland as a wedding present to one of the daughters of Castle Forbes House in Longford in 1911. From there they were believed to have been intentionally released into the countryside and have subsequently spread across Ireland into Northern Ireland both naturally and by intentional further introductions. Only large water bodies such as the Shannon River have hindered their spread.
  Red squirrels are native to Northern Ireland and are believed to have been present here since before the last ice age, but had become extinct a number of times. Historically the removal of native woodlands has undoubtly helped to cause their decline, through the removal of suitable habitat and food source. In an effort to re-establish red squirrel populations in Northern Ireland in the 19th century they were re-introduced from Britain.
  The red squirrel is however once again under threat, but this time it is from it’s larger north American relative the grey squirrel.
  So why is the grey squirrel a threat to its smaller relative the red squirrel?
  Firstly the grey squirrel competes with the smaller red squirrel for habitat space and food. The grey squirrel is capable of eating unripe food sources earlier in the season, such as acorns, whilst the red squirrel needs the food source to be fully ripened. By the time the smaller red squirrels are ready to eat the grey squirrels have cleaned up most of the food supply leaving very little for the reds.
  The second reason is that the grey squirrels can, in some cases, carry a virus known as the ‘Parapox virus’ or ‘Squirrel Pox’ to which they are immune. They can pass this highly contagious virus on to the red squirrels, who are not so fortunate and do not have natural immunity. An infected red squirrel will develop severe very sore lesions (open wounds), which will eventually lead to their death in a very short period of time. It has been one of the most significant factors in the decline of red squirrel populations in G.B. but so far, not in Northern Ireland.

Q. How will climate change affect our wildlife in Northern Ireland?

• A. Higher summer temperatures and milder winters are likely to result in movement of cold-adapted species which are at the southern edge of their range in Northern Ireland both northward and upward in altitude. In the long term, some may not be able to find suitable habitat and may be lost. Conversely, more southerly species adapted to warmer conditions are likely to become established here. Many native species are likely to breed earlier but may become increasingly out-of step with the emergence of the food supplies on which their young depend. Drier summers will adversely affect many wetlands while some river-dwelling species, such as the Salmon, may be vulnerable to the effects of flash floods caused by more frequent extreme weather events. Winter migrants from the north may become less abundant as milder conditions allow them to remain closer to their breeding grounds. Rising sea-levels will threaten scarce coastal habitats such as saltmarsh and sand dunes.

Q. What are the 5 rarest species in Northern Ireland?

• A. The Fan mussel (only one living specimen) a shellfish in our local seas, The Irish whitebeam, a very uncommon tree. The purple saxifrage is a beautiful alpine plant that grows at one site on a sheer cliff along the North coast. The whiskered bat is a very rare mammal which has its only Northern Ireland colony in a County Fermanagh Church. One pair of Chough, a member of the crow family which has a red beak and feet nested on sea cliffs on Rathlin Island in 2008.
  

Q. Why are there no snakes in Ireland?

• A. Legend has it that St. Patrick banished serpents from Ireland. The other explanation is that following the end of the last ice-age, during a time of very rapid climate change about 10 000 years ago, North-west Europe was all one land mass, as the climate got warmer species from central Europe naturally spread noth and west, however at the same time, as the ice in the seas melted so sea-levels began to rise and flood low lying areas. Low lying ground between Ireland and Europe was flooded before snakes colonized this newly formed island.

Q. Which is the oldest tree in Northern Ireland?

• A. There are several very old or ‘veteran trees’ in Northern Ireland. The old oak at Cranmore (meaning more – big, Cran – oak) is reputed to be over 500 years old. The Crom Castle Yew trees in County Fermanagh are believed to be over 800 years old.

Q Why are ‘peatlands’ such important habitats?

• A. Peatlands are habitats which form under certain climatic conditions where vegetation growing on waterlogged ground builds up to form very deep deposits of plant debris known as ‘peat’. The peatland surface provides a habitat for special ‘bog building’ sphagnum mosses and other wetland species. This habitat is limited in its distribution throughout the world and a number of unique plants and animals have developed close associations with our local peatlands.

Q Are there any sharks in our local seas?

• A. There are almost 20 species of shark found in Northern Ireland waters - the basking shark is a common summer visitor, it is the 2nd largest fish in the world and feeds entirely on microscopic plankton which it filter feeds. From skates, rays, dogfish and cat sharks to tope, basking and blue sharks…… there are many resident and passing species.