The old cliché perhaps that we know the cost of everything know but may not know the value of our natural environment including the needs for clean unpolluted rivers with a hydro-geomorphological (HGM) profile and water quality suited to abundant populations of wild Atlantic salmon.
Where would economic progress be without alteration to the hydrogeomorphology of rivers. For example, land drainage, coniferous forestry, infrastructure developments, hydro-electricity, mining, and others tip the balance against freshwater salmon habitat. Very few if any rivers throughout Ireland contain previous abundances of Atlantic salmon’s preferred freshwater nursery habitat. Many sections of many rivers have been straightened taking away meanders, resulting in increased spate water velocities often which reduced water levels in droughts and increased erosion leading to unhelpful fine sediment depositions and destruction of preferred salmonid habitat of pool riffle glide sequences. In essence management of the riparian catchment can easily compromise river water quality and hydro-geomorphology profile. Salmon management plans need to mitigate against habitat destruction of salmon habitat.
Correlations and statements suggesting that economic progress stresses the natural environment are not new and have been presented and discussed for years at many scientific and fishery meetings. Critically Salmon management plans have not yet secured the required turnaround in the fortunes of Atlantic salmon in Ireland as the salmon population abundance continues to decline#. We now need to prioritise Atlantic salmon needs more now than ever or simply watch the species decline to a level of rarity. ) IUCN endangered)
A key question is are clean rivers and abundant salmon runs important to society, local communities and sustainable living when balanced against other essential economic priorities? Everyone probably has an individual answer to that question though not all will appreciate nor understand the bigger environmental / sustainability picture tending to focus on basic needs of food, shelter, self-esteem and self-actualisation as famously described by Maslow in his hierarchy of needs for personal survival. Balancing economic decision making against environmental and ecological essentials is challenging.
As a lifelong angler for Atlantic salmon and with memories of local abundant catches of wild Atlantic salmon, around Ireland, I ask if salmon conservation measures are sufficiently delivered to reverse the terrible negative decline in populations. Many, though declining numbers of anglers throughout Ireland and NI buy a salmon licence and permit for the privilege of catching in our rivers, or in recent years not catching Atlantic salmon.
Many individual river salmon populations are severely diminished, some more than others. There are many reported complex reasons for diminished returns of adult salmon to natal rivers. Climate change, increased water temperatures in both marine and freshwater have a negative impact, and it is widely reported that juvenile salmon suffer from heat stress when freshwater water temperatures reach 18- 20 degrees centigrade. Also, it has been recently reported that the sea temperature in Norway has increased to 4 degrees above normal with strong evidence in an explosion of the sea lice parasite with negative consequence on the morbidity and mortality of smolts at sea.
Whilst protection and sustainable management of salmon populations at sea is essential it is at least equally essential to ensure that individual rivers provide sufficient physical habitat to facilitate abundant juvenile productivity. Decision making around salmon management is dependent upon a scientifically derived conservation limit. The conservation limit defines an egg deposition level required to ensure smolt output. River habitat therefore needs to be protected to theoretically ensure returning adult have somewhere to deposit their ova ( spawning habitat ) and to accommodate all the freshwater life cycle units ( ova, fry, parr ,smolt) Essentially ,in addition to protection of maturing and returning adults at sea and chemical pollution prevention measures defined within the Water Framework Directive the hydro geomorphological profile of individual rivers also needs protection as the physical habitat defined by spawning, nursery and holding habitat for secure residency of adult fish awaiting spawning time ( NOV/ DEC)
It is unlikely that rivers can be fully restored to their preindustrial HGM profile within management catchments. Where salmon preferred HGM profiles still exist they now need maximum protection, particularly with sea return rate being so low. Therefore, in addition to improving the water quality and riparian catchment management in rivers the hydrogeomorphic (HGM) profile best suited to salmon needs protection. If not, the productivity form individual rivers is likely to continue to decline and the salmon abundance at sea will be further diminished.
Defining a HGM profile of a river from a salmon management perspective involves assessing the physical habitat structure in terms of life cycle stage needs for ova deposition, fry, parr and smolt migration and residence for returning adult fish prior to spawning time ( Nov/ Dec). Holistic management of salmon stocks requires an audit of these habitats as a means of defining the potential productivity of each individual salmon river. Each individual river needs its own salmon management habitat plan supported by a holistic management of stocks at sea. Angling clubs and community groups need to define the local priorities with a strong weighting given to the habitat needs of Atlantic Salmon in the evolving WFD planning process.
The UK and Ireland are tasked by the overarching WFD guidance to determine their own local environmental improvement goals. The opportunity exists now to ask why the last three WFD planning phases have failed to achieve the key goal of good ecological status and input into a plan for the fourth planning cycle. It is probable that the COVID lockdown impacts in 2020 reduced consultation and contributed to a lack of attainment of WFD goals.
In addition, the most recent programme for government for NI has prioritised the public sector as a key enabler to grow a globally competitive and sustainable economy. It is a concern in NI that there has been a deterioration in achieving the defined Water Framework Directive (WFD) goals in recent years most noticeable in NI with the algal bloom in lough Neagh. Over many years I have heard it said by some that the locally defined WFD targets are overambitious and by others that they are realistically achievable over the time frame. However, it is clear now that NI is failing to achieve the WFD targeted outcomes, although the salmon management plans reported (AFBI) suggest that three rivers in NI are achieving a conservation limit (CL) surplus allowing a small harvest of Atlantic salmon. AFBI reports that the population in all other rivers is greatly diminished and well below the defined management target and conservation limit.
The office of Environmental Protection report ( Sept 2024) is critical of the WFD implantation process in NI and highlights a lack of specific plans for individual rivers and catchments. The failure to manage freshwater pollution in NI is reflected in a failure to achieve successful attainment of the WFD goals to attain good ecological status in NI rivers and currently noticeable within the context of the recent Lough Neagh toxic blue green algae bloom. Consequently, fishing communities in lough Neagh have been severely impacted. As a lifelong salmon angler I ask if the failure of WFD implementation plans have also negatively reduced the effectiveness of salmon management plans in NI. I provide find some thoughts and analysis about the WFD objectives and established objectives (defined as programmes of measures in WFD) and how these align with Atlantic salmon management objectives Ireland with reference to NI, and the North Atlantic Salmon Conservation Organisation (NASCO) goals.
Atlantic salmon habitats consist of a marine phase (Maturing and returning adult) and a freshwater phase (necessary for juvenile recruitment and productivity). In recent years research suggests that survival of juvenile to adult in the marine phase is compromised and a major cause of reduced abundance of adults returning to natal rivers. However, since protection of the freshwater river phase is dependent on the WFD programme it’s a concern that freshwater habitat is also neglected. Growth of abundant adults at sea requires recruitment of abundant juveniles from rivers. Protection of freshwater river habitat is therefore vital to ensure sufficient recruitment of juveniles to sea. Any salmon management plan relying of good freshwater habitat functions within the WFD context. The WFD therefore needs to facilitate the needs of Atlantic salmon within it’s programmes of measures as an essential component of Good Ecological Status (GES), a key measure of WFD success.
Good Ecological Status (GES) a difficult term to define https://www.ecrr.org/River-Restoration/Flood-risk-management/Healthy-Catchments-managing-for-flood-risk-WFD/What-is-the-WFD. It is argued here that achieving GES necessitates providing for the biological and ecological needs of Atlantic salmon which are ubiquitous Ireland’s rivers. However, a large portion of the WFD deployed resources are targeted at reducing eutrophication specifically, achieving target boundaries for phosphorus, nitrates( NAP , PAP) and new and emerging pollutants. The classifications of good, poor, bad are defined by boundary concentrations of chemicals for each classification. Defining biological and ecological status is less specific within the WFD context and is influenced by popular and fashionable economic priorities.
Rebuilding Atlantic salmon populations requires ambitious implementation of strategic plans to rebuild Atlantic salmon populations. Therefore, protection of freshwater habitat is as important as the protection of marine habitat. Although the relationship between the various juvenile freshwater life cycle stages,(ova, fry, parr, smolt) is complex, the quantity of suitable habitat will limit juvenile output to the marine phase as smolts.
Harvest opportunities are determined based a conservation limit scientifically defined as the number of adult female salmon (as ova, approx. 500 / kg of adult female) needed to ensure that a particular river is sufficiently populated with juveniles. The potential juvenile productivity will be defined by quantities of suitable habitat, unpolluted and reflected by the HGM profile.
Juvenile habitat can be defined as fluvial (river area) area and requires good water quality free form pollution to be productive. However, the specific quantities of habitat types for specific life cycle stages (spawning, nursery, pools) will vary from river to river and determine potential juvenile output. Individual rivers will contain their own unique Hydro geomorphological (HGM) and productivity potential for Atlantic salmon will be reflected in HGM profile. Thus, certain rivers have the potential to produce more juvenile salmon than others in relation to HGM profile ( ie quantity of spawning, nursery and pool habitat and their proximity to each other) where water quality is good. For example, effective ova deposition by mature female fish requires spawning habitats defined by a specific gravel size and flow rate often found in glides at the tail of pools and in shallow riffles. Fry, parr and smolt require various grades of hydro-geomorphological structure nursery habitat to thrive optimally. In addition, adult salmon require pools to reside in prior to spawning in late autumn and winter.
Good water quality and lack of pollution are essential to ensure optimum output from the HGM habitat zones (spawning and nursery). Ultimately the quantity of freshwater habitat in rivers will limit the productivity of juveniles within any catchment and will also be impacted by poor water quality. It is therefore vital to maximise appropriate freshwater habitat to maximise juvenile recruitment to the ocean to ensure an adult return rate necessary to ensure sustainability of adult Atlantic salmon to individual rivers. Anti-pollution measures and protection of HGM profile are therefore critical to ensuring a future for Atlantic salmon in Ireland. Riparian zone management such as infrastructure projects, drainage, forestry, are all possible stressors in addition to climate and ecological factors. Peak to trough flood events will also impact productivity which may vary from year in relation to rainfall and drainage. Fine sedimentation into habitat is also problematic as this will impact river gravel resulting in salmon nests ( redds) being difficult to excavate by spawning fish and impact the hatching of ova to the alevin stage of the life cycle.
The WFD is tasked with improving river water quality to acceptable levels of ecological status which must include the ubiquitous salmon populations in Irish rivers. Some suggest that protecting freshwater habitat will make little difference to salmon stocks when sea survival rates are so low. However, how can stocks ever recover if freshwater habitat for spawning, nursery growth and residence of adults prior to spawning is not protected also.
I therefore make no apologies for supporting a practical focus on protecting nursery habitat for salmon in rivers where local communities and salmonid angling interests represent community desires and rights to maintain salmon populations in local rivers.
The WFD is provides strategic guidance to achieve improved status of rivers across Europe and continues effect its influence in N. Programmes are delivered by DAERA and affiliate organisations. NASCO provides the international overarching umbrella organisation for Atlantic salmon management, delivered by DAERA and its affiliate organisation.
Each river requires it’s own unique environmental objectives including developing anti-pollution measures and definition of unique HGM profiles. In NI a method utilizing the RHAT model could be modified to assess salmon habitat profiles of individual rivers as a key cog in the development of salmon management plans.