‘ON THE RUN’
Late spring melts into the first rays of summer sunshine heralding the annual run of sea trout and salmon into West Highland sea lochs.
It is late May early June and shoals of sea trout are well inshore cruising the righthand shoreline closely following the contours.Foraging for sandeels and other tasty foods.In no obvious haste to reach their destination progress is slow and methodical as they journey along the coastal reaches resting up in sheltered bays or freshwater inlets before moving on.
Low tide is an ideal time to search out holding bays.Sea trout are often seen ‘splashing’ -feeding on whitebait and other fry at slack water close to shore.Occassionaly found over sand sea trout prefer areas of broken rockand weed to rest in providing cover from predators and as a food source.
As the tide floods shoals of sea trout congregate together swimming downtide to settle into favourable lyes further on.Perhaps only the next bay or the bay beyond.Other fish follow on behind competing for the best lyes constantly pushing those to the front onward.
Their numbers grow daily as other smallshoals run in from the open sea.Over the oncoming weeks most inshore lyes play host to resident populations of trout as the main run gathers momentum.By early July the fore-runners of the main shoal reach their chosen estuary and birth river.
Sea pools are the lowest estuarine pools of a river that flood with the oncoming tide and drain with the ebb tide.Moon phases regulate tidal flow which in turn controls movement of fish to and from the pool.
Once a month there are phases of full and new moon which draw the highest tides,known as springers,carrying fish into the system both day and night.Most fish are reluctant to run the pool during neap tides which are the lowest of all.Tidal water running between springers and neaps carry a sready influx of sea trout and salmon into the system too.Though less fish are evident in comparison to that run with a springer.
As the tide turns from slack water to flood a small percentage of sea trout make their way from holding bays nearby in the estuary.Small shoalsgather anxious to forge on upstream and into the sea pool.Saltwater backs up the river slowly raising levels to a point where the trout know instinctively that they can with confidence.As the tide gathers momentum other trout too run directly from the open sea into the sea pool.Until the tide has run it’s course.
Some fish show as they splash through the run-off many otthers simply hug the bottom slipping quietly and un-noticed into the main pool.An occassional stray bow wave the only other sign of activity.
Introduced to the brine mix of salt and freshwater the trout perform a ‘ritual’.
Leaping high and clear of the water,racing round the main body of the pool their silver flanks reflecting in the sun,most show themselves once again in the run off then settle down into suitable lyes.
A steady influx of fish carried on the tide access the pool.Activity is intense for long periods coming to an abrupt end as slack water peaks.At which point the fish exit the pool on the ebbing tide.Some stay close to the river mouth others find their way into holding bays to await the evening tide.Surprisingly sea trout display a high degree of confidence within the sea pool during daylight hours.For a week or more continous streams of fish migrate from open sea to the sea pool and back again.A gradual transition from salt to freshwater reversing the osmosic process acclimatising the trout to their future dependancy in freshwater.
Trout accustomed to to the tastye of freshwater hold oin the pool waiting for the opportunity to run upstream when suitable conditions are prevalent.
Sea trout require only minimal water levels in which to run and a few slip into the river system every night.Most however prefer to wait patiently in the sea pool for conditions to improve running under the cover of nightfall,heavy cloud cover or a rising river.Covering two miles per hour travelling between pools.Only when the river levels are suffering severe drought conditions will seas trout dfecline to run.
A new moon rises to a 4.0 metre spring tide coinciding with darkness.Water levels are good and the skies overcast.Sea trout carry in on the flooding tide and the sea pool is ahive of activity.
In the darkest hours trout are extremely wary cautious and easuily ‘spooked’ Running the river is tonight’s aim a quest that may take several hours before meeting with success.Small shoals congregate in the shallows toward the head of the pool.Occassionaly one or more trout break away hanging mid-stream testing the ground before dropping back to join their companions.A routine repeated over a period of ten to fifteen minutes.
At this point one of two things may occur.
The whole shoal turns away heading back downstream into the main pool or the leading fish go through the run-in.Their backs proud of the water.Tails thrashing hard against loose gravel in a flurry of spray signalling the others to follow on.Moments later another shoal of trout assume their positions at the head of the pool and the same scenario is re-enacted,as it will be many times throughout the night.
Bow wave upon bow wave precede the trout as they swim gently on through slow glides and moderate runs journeying upstream.
A shallow bar of gravel barely covered with a trickle of water obstructs the intrepid travellers.With an extraordinary burst of speed tails thrashing hard to propel them forward the trout mount the loose stones.Progress is slow.Each stage tackled with small bursts some scraping their bellies other flapping on their sides in an effort to reach deeper water.Such is their determination.
Eventualy reaching the uppermost tidal reaches where pure freshwater spills into the brine,resting for a while in sdlack water.Once again one or two trout take the initiative taking the lead and break away from the main shoal.Testing the ground.With a flick of their tails the lead trout push forward through the run-in and into the river.
The point of no return !
Once commited to freshwater they journey on without turning back overcoming whatever obstacles they encounter on the way.
Throughout the night many small shoals instinctively follow in their wake.
At about 1.00am sea trout become less active and tend to be lethargic.The run resuming again an hour or so later.At any given time fresh fish access the main pool,trout running the river and others that simply lye up,and those that drop back downstream sand back to sea.When conditions are poor such as periods of drought the pool will be quiet with little activity.
Spate water draws fish directly into the pool during daylight hours inducing them to run hard and fast.
False dawnbreaks cloud cover at about 3.00am as the first rays of rthe coming day shine down.No matter what stage the tide is at fish stop running.Dropping back downstream from the sea pool into the estuary making their way to nearby holding bays.
Fish in the upper tidal reaches make their final bid for freshwater.Struggling on until deeper cover with cover is found in which to lye up in awaiting the next tide.Taking refuge under undercut banks,behind rocks,in shallow depressions.Preferably under the cover of streamy well oxygenated water and csan be found in the most unexpected places !
By 3.30 am dawn encroaches fast and there is little if any movement.A time to rest patiently waiting nightfall.
July and Aufgust see many sea trout run through the system.Some rivers are fortunate having a second run of trout in September.