Strandloper Project survey sites in the garden Route

Documenting the different methods of fishing tackle snagging.

Since the onset of our reef surveys for snagged recreation fishing in January 2018, the Strandloper Project has been able to distinguish a variation of snagging causes which are influenced by three different factors, namely targeted fishing focus, socio-economic factors and the reef type.

Strandloper Project volunteers sorting through fishing tackle recovered from our transect at Gericke’s Point

Besides the obvious snagging effect of a reef, two additional major aspects which influence the rate of tackle snagging for shore based rod fishing are firstly the reef community composition and secondly the focus of target species. The latter aspect influences both the size and setup of the tackle. Within this latter aspect, in the Garden Route, there is a socio-economic influence which has to be considered.

Subsistence fishermen, at the lower end of the socio-economic spectrum, by necessity, have to catch fish on a daily basis if they want to supplement their diet with animal protein. Using cheaper tackle setups and smaller hook sizes, they also target small to medium size fish. In essence, 1kg of fish, whether it is 10 x 100g fish, 20 x 50g fish or 5 x 200g fish, is still 1kg of fish.

By contrast, sports fishermen tend to target medium to large fish wanting either a large fish or a trophy photo. As a consequence of these objectives, hook size and rig setup is more complex and diverse depending on the species and size of fish targeted, with tackle costing up to R80.00/setup.

The range of sinkers recovered by the Strandloper Project is indicative of the socio-economic factors which influence tackle setup.

A consequence of the variation on setup as determined by budget, also has an influence on the fishing site, with ease of access, proximity to fish shoals and distance from home playing a crucial role for subsistence fishers. With some subsistence fishers relying only on handlines, their fishing sites tend to focus on jetties, locations with narrow reefs and rocky shores close to reefs.

For our Strandloper Project research we have focused on three research sites between Knysna and Gericke’s Point, with a site near the Paquita Wreck, one in Kingfisher Creek and the primary site at Gericke’s Point.

The three sites have distinctive reef communities with the Paquita site dominated by Red Bait, the Kingfisher Creek exhibiting a mix of sand and reef stacks colonized by mussel communities. Gericke’s Point is a mix of aeolianite shelf extending out to a sandy seabed with sections of broken aeolianite blocks between the shelf and sand bed. The aeolianite is colonized by marine flora with a predominance of red algae, though Red Bait and mussel beds colonize sections within a depth influenced by the tidal range.

Knysna Heads

In the Knysna Channel, the reef is colonized by a Red Bait from the shoreline to the sandy seabed.

In the zone that extends from the shoreline to the sandy seabed, the majority of snagged fishing tackle that we have recovered has been caused by the hook becoming imbedded in the Red Bait pods, effectively eliminating any threat of ghost fishing from the tackle. In the deeper water further away from the shoreline and over the wreck infrastructure, the snagging is a mix of hooks embedded in Red Bait and sinkers snagged on solid structure and reef colonies.

A typical case of snagging occurring when the hook embeds in a Red Bait pod in the Knysna Heads.

A sinker rests on the reef when the hook becomes snagged in a Red Bait pod.

The mix of improvised items used as sinkers is indicative of the socio-economic group that regularly fishes from the rocks near the Paquita Wreck in the Knysna Heads.

Kingfisher Creek.

Most of the shoreline fishing tackle snags on the mussel beds on the aeolianite stacks, again with the primary method of snagging when the hook embedded in the mussel beds. Though this snagged tackle presents little or no ghost fishing threat due to ingestion of lost baited hooks, the sections of monofilament do present an entanglement threat to diving species of birds (mainly cormorant species and Little Grebe) that hunt fish in the channel.

In the channel leading to the Swartvlei Estuary mouth, the hooks embed in the mussel and oysters encrusting the aeolianite columns.

The holiday influx over December and the Easter Weekend is reflected by the increase in lures and spinners recovered.

Gericke’s Point

The maritime map name for this site is Lion Rock due to it’s distinctive reclining lion or sphinx like shape when viewed from the north east. The more commonly used name of Gericke’s Point stems from the late 1960’s in reference to a land surveyor, Mr Gericke, who regaled land owners of his fishing exploits at the point. A combination of easy access and historical accounts of great catches, make this site a popular shore based fishing location in the Garden Route.

Lion Rock sports a shape that resembles a sphinx or lion when viewed from the north east.

The Strandloper Project has a 100m transect along the reef shelf that we conduct all our dives on. Though accessibility to dive on the site is influenced by sea conditions, the Strandloper Project volunteers manage to conduct an average of 8 dives per year at this site.

In the survey period there has been an increase of braided line used in tackle set up. This poses two risks to marine life, firstly scraping reef organisms off the fixed substrate. Secondly, the duration of the braided line extends the duration of the threat of entanglement of avian species that hunt and forage on the reef.

Hook size is indicative of both what size fish is being targeted and the socio-economic group that frequents Gericke’s Point for fishing.

Along the 100m transect line, approximately 20% of snagged fishing tackle is recovered from a single rock in the high cast zone. In addition to the risk of ghost fishing presented by float assisted baited hooks drifting above the reef, the accumulation of sinkers results in lead poisoning of the communities attached to the reef. This, combined with the drag impact of tackle being recovered in the high cast zone, destroys flora and fauna marine organisms.

One of our most valuable reef clean up dives through the year is our Baseline Pre Season dive. Conducted at the end of November. On this dive we attempt to clear as much snagged fishing tackle from our survey transect as possible so that on our follow up dive in January we get a indication of the impact of the holiday influx on the reef and the eco system that it supports.

Post season clean ups have a recovery of over 1 sinker per meter along the 100m transect. This is approximately a 20% increase in the out of season snag rate.

The amount of snagged recreational fishing tackle required a system to simplify the collection and carrying of the tackle while diving. A tethered bucket with an inner tube to float it has been very succesful.

The mode of snagging at Gericke’s Point is that the sinker hooks on the rocky reef at the transition from the sandy seabed to the reef. The use of floats on the baited hook is regularly used by sports fishermen at Gericke’s Point, presenting an increased risk of ghost fishing.

Of the 11 species of fish that the Strandloper Project has documented, 8 are shark and ray species. This endemic Pajama Catshark was fortunate that we found it before it died. We managed to remove the hook and liberate it.

Biodiversity Hotspot

The focus of all our dives are to clean the reef of snagged recreational fishing tackle and to analyse the items recovered. Obviously, while spending time along the reef, some spectacular marine sightings are made.

Our volunteers have been fortunate enough to swim with both a Green and a Hawksbill Turtle. Annually there is breeding aggregation of Blue Stingrays along our transect at Gericke’s Point. The hype about sharks focuses on the larger species, but in reality it is the smaller catshark and shyshark species that we see more frequently.

A juvenile Dark Shyshark rests in a reef crevice.

On the undisturbed sections of the reef, the macro fauna abound with over 10 species of nudibranchs recorded, three species of flatworms and various anemones to capture for avid underwater photographers attention.

To assess the condition of the reef, Strandloper Point conducts a series of fixed point photography surveys. The site above has revealed some amazing insights to reef regeneration. In 2014, the site was barren of any algal and coral growth. In December 2019 significant sea fan and red coralline algal growth had occurred. Studies suggest that the regeneration of the reef is an indirect result of climate change, With a climate change induced drought in the Garden Route, the blind estuaries have been closed longer than they are open, a direct reversal of their status during the wet period. With less water from rivers and estuaries entering the ocean, there is an associated decrease in agri chemicals entering the sea which could be a contributing factor to the regeneration of the reef.

Discarding Culture

Not every fish caught is a desired species, with some species considered by fishermen to be a pest that steal their bait. Sadly, there are still some fishermen who simply discard unwanted species on the shore, leaving them to die. Most discards are small shark species, skates and Sea Barbel.

In terms of marine biodiversity and productivity, numerous studies have demonstrated that a robust and healthy shark population is conducive to an increase in both. The culture of discarding sharks and rays needs to change and the perpetrators be educated by ethical anglers to modify their behavior.

The reproductive stratergies of sharks and rays make them particularly vulnerable to over exploitation. A Spotted Gully Shark lives for 21 years reaching sexual maturity at 14 years. The female will bear between 6 to 12 pups after a gestation of just under two years.