A Limited Study Of Boat Anchor Disturbance And The Need for Installation Of Moorings in Central California
by Jesús C. Ruiz, A.A.U.S.

 Introduction

While substantial research has been done on the disturbance to benthic marine life and its effects on Coral Reefs caused by dive boat anchoring in Tropical areas, no study of boat anchor disturbance in the Central California waters was found to exist. Therefore, three questions must be answered: 1.) Does anchoring from dive boats do significant damage to the benthic marine life in the Central California temperate waters, to warrant the installation of moorings? 2.) If a test mooring was to be placed, where should it be, and what are the characterizations of that dive site? 3.) What are the logistics of placing a mooring? These questions were studied and the results analyzed and discussed below.
 
 Significance
The Monterey Bay area in Central California is an active recreational scuba diving
destination with a reported 60,000 annual diver visitations alone within the Monterey Cannery Row vicinity. Diving is an important contributor to the economy of the Monterey Bay area, and a significant recreational activity. Recreational scuba diving is dependent on healthy marine life, healthy dive sites and a healthy community environment, in general. Most all dive sites are within the jurisdiction of the Monterey Bay National Marine Sanctuary, within the jurisdiction of several California State Agencies, and over lap with several private and commercial users of the coastal waters. Commercial charters and private boats take divers to various dive sites from Monterey to south of Point Sur. The benthic marine life at most of these dive sites are subject to anchor disturbance on a continual basis. It is important to know if this anchoring disturbance is adverse and detrimental to the health of the marine environment, or if anchor impact  to the benthic life from continuous boat anchoring is non-detrimental to this temperate environment, and thus, insignificant.
 
 Methodology
 In order to determine the impact from boat anchors to the marine life in the Central
 California temperate waters, a preliminary study was conducted to witness, photograph and video tape the disturbance of an anchor and chain from a dive boat. A dive charter was used to document  anchor impact during actual dive runs at common dive sites. Three dives were conducted down to the anchor impact point, each in advance of, and prior to,  passenger scuba divers entering the water. Once in the water, the scuba divers stayed away from the anchor study site and its chain. A fourth dive was performed, after all diving passengers were on board,  to witness the routine lifting of the anchor. The first dive was at Que Paso Pinnacle, where the anchor landed at 70 feet in depth, but the chain dropped and looped to a depth of 88 feet. The visibility at Que Paso Pinnacle on this day was about 25 feet horizontal, and the surge was moderate. The anchor and chain were deliberately left loose and allowed to drag and move against the substrate for the purpose of testing. This deliberate slack simulated occasional slack and drag which occurs on boats due to an unstable anchor or wind shift. After a ten minute slack period, the chain and anchor were tightened as in usual anchoring procedure for scuba diving vessels.
 The second dive  was at Lobos Rocks with a maximum depth of 48 feet and the anchor
 resting on the side of a rock at a depth of 45 feet. The visibility at Lobos Rocks on this day was about 20 feet horizontal and the surge was moderate. Again, the chain was allowed to remain slack to repeat the simulation of the occasional boat shifting and chain dragging. After a ten minute period, the slack was taken up and the anchor grasped the bottom as in all routine anchoring.
 
 The third dive was at Lobos Rocks, on the same spot as the second dive, and as part of
 the passengers still on going second dive. The maximum depth was 60 feet and the anchor sat at 60 feet. The anchor dragged from its original 45 foot setting to rest against the side of a rock at 60 feet. The fourth dive was at Yankee Point’s Pinnacle of Tremendous Proportion (PTP). The visibility at PTP was about 4 feet with heavy surge action, and the current was extremely strong. After all the passenger divers were back on board, a dive to the anchor point was performed to witness the lifting and retrieval of the dive boat’s anchor from a depth of 30 feet.
 All dives were executed with the use of EAN-Nitrox 32% Oxygen blend. On dive
 number one and two, one research diver used a video camcorder and the second diver took still photography on transparencies. On the third and fourth dive, both divers shot video. Some still photographs have been extracted from video clips of all the dives. The diving vessel used for this research is 60 feet long, 16 feet wide, and weights 58 gross tons. The anchor is a BRUCE Anchor weighting 30 kilograms. The chain is 40 feet long and one half inch in diameter.
 The characterization of Eric’s Pinnacle was performed by running three transect line
 from the top of the pinnacle towards the base to a maximum depth of 60 feet. One transect line was drawn at zero degrees North, the second transect line ran at 120 degrees, and the third transect line ran at 240 degrees. A one square meter quadrat was used to do  random sampling of the habitat along the transects to collect quantitative and qualitative data of the algal and invertebrate life on Eric’s Pinnacle. Underwater slates with data sheets, photo sheets and the "Habitat Assessment: Percent Cover Sheet" were used to collect data. Together, both divers ran the transects, and one diver carried and placed the quadrat. The second diver carried the underwater slates, counted and noted the data onto the "Habitat Assessment: Percent Cover Sheet." Percent cover of small invertebrates and small algal was estimated from the series of drawings in the Habitat Assessment sheet depicting 1-5%, 6-25%, 26-50%, 51-75%, 76-95% and 96-100% of the quadrat area covered. Large invertebrates, like the rose anemones (Urticina lofotensis) and large algal, like Pterygophora, californica were individually counted. Each transect required a separate dive, for a total of three dives at Eric’s Pinnacles. Each dive commenced at the base end of each transect and the count was performed by diving  upwards towards the top of the pinnacle. The visibility was about eight to twelve feet horizontally, and the surge was moderate. At request, a mapping of Eric’s Pinnacles was performed by Rick Kvitek, Marine Science Professor at California State University, Monterey Bay. The mapping was done by using a Reson 8101 Multi Beam Sonar with a 150 degress beam angel, and the data was processed in CARIS HIPS Software.
 
Analysis
Does anchoring from dive boats do significant damage to the benthic marine life in the Central California temperate waters, to warrant the installation of moorings?

During the SCUBA dives at Que Paso Pinnacle, several episodes of anchor and chain disturbance were noted. The chain nearest the end of the anchor landed very close to one hydrocoral (Stylaster califonrnica) filmed on this dive, but no contact was made with the hydrocoral (Stylaster califonrnica). The arm of the anchor landed on a stipe of Pterygophora, and 5 to 6 inch scrapes were evident along the length of the stipe base. In front of the anchor blade a fluted bryozoan (Hippodiplosia insculpta)  was stationed, but at this time, no impact had be made with the bryozoan(Hippodiplosia insculpta). The arm of the anchor laid downward along a rocky wall covered with more bryozoan, strawberry anemone
( Corynactus californica), sponge, and articulated coralline algae (Calliarthron tuberculosum) , but touched only the encrusting algae (Pseudolithophyllum) and encrusting coral (Paracyathis stearnsi). The chain hung downward between stipes of Pterygophera, macrocystis, and, sea star(Pisaster), Laminaria and on occasion, the chain would touch the top of a rocky surface with encrusting coralline algae. The chain was witnessed moving back and forth length wise as it bobbed with the swell movement.
 
On dives at Lobos Rock, the anchor first landed against a rocky wall covered with strawberry anemones and White Spotted Rose Anemones, and Pterygophora was plentiful around the anchor, but touched only the encrusting algae and encrusting coral. One of the anchor’s wings also leaned against some strawberry anemones. About half a dozen white spotted rose anemones lay near the anchor, but unharmed. Macrocystis rose from that rocky bottom to the surface. As the chain initially dropped downward during the planned ten minute slack period, the chain ran alone the stipes of Macrocystis and between the stipes of Pterygophora, and past a fluted bryazoan and over a bed of Red Fleshy kelp. A three to four inch long abrasion was witnessed on one stipe of Pterygophora adjacent to the chain. At the spot where the chain hung over the Red Fleshy kelp, then downward, before turning toward the surface, there was no movement of the chain, no scraping of the bottom, and no side way movement. The chain then hung in the open water as it gradually rose to the surface towards the boat. At that point, the wings of the Pterygophora brushed and slid along the chain, but no loss of kelp was noted.
The third dive was again at Lobos Rock. The anchor dragged from its original position at forty five feet to sixty feet. In the process, it scraped the surface of the rocky bottom leaving a one half inch by four to five inch mark on the rock. The arm of the anchor lay on encrusting coral and one of its tips rested on a white spotted Rose Anenome. The anemone remained open for the duration of this episode, and it did not retract nor look torn, cut nor lacerated. The several stipes of Macrocystis lay under the chain as they reached for the surface. Again, some stipes of Pterygoghora appeared scraped by the anchor near the chain. The chain did not scrape and drag across the bottom, but rolled sideways with the movement of the surge. As it went over strawberry anemones, Pisaster, Laminaria, and Red Fleshy kelp, none of the bottom appeared impacted, harmed, nor damaged by the chain. Some, but not all of the strawberry anemones would close up. The kelp rested under the chain, and when released, swayed with the surge. No hydrocoral was seen on this dive.
The fourth dive at Yankee Point’s Pinnacle of Tremendous Proportion (PTP) exhibited a lot of Eisenia arborea, Pterygophora, Fleshy Red Kelp, strawberry anemones, some sea stars, and an abundance of articulated coralline algae. Upon lifting, the anchor ripped away Fleshy Red kelp and articulated coralline algae. It then swung around and scraped the side of the rocky wall covered with strawberry anemone, and more articulated coralline algae. It is difficult from the video clips shot  of this second scraping to determine whether the anchor scrapped off articulated coralline algae or Corynactis californica. The debris was white in nature and it appeared  similar to the scrapping to that of the initial lifting of the anchor. Attempts to retrieve close up video shots of the top impacted areas proved impossible, in that the Red Fleshy Kelp turf was abundant, and it covered over the articulated coralline algae. On the side impacted area, the strawberry anemones covered a large area, and there were also equivalent areas of articulated coralline algae. Neither of the anchor impacted areas were recognizable for a comparative analysis.
Accumulative, from the four dives, the following adverse impacts were noted:
1. The anchor landed near, and on stipes of Pterygophora, causing them to bend and scrape.
2. The anchor and chain leaned against strawberry anemones, and rested on a White Spotted Rose Anenome.
3. The anchor scraped the surface of the rocky bottom, scraped off Fleshy Red kelp and Articulated Coralline algae.
4. The anchor landed very close to a Hydrocoral and a Fluted bryozoan.
       While this noted anchor and chain disturbance appears to be adversely affecting the bottom, the question remains whether anchoring from dive boats do significant damage to the benthic marine life in the Central California temperate waters to justify the installation of moorings? A more critical analysis of the affects of these impacts sustained by the fauna and flora at these dive sites is needed, but a preliminary review of the current available literature on this subject provides insight for contemplation.
 
While initially there appears to be cause for concern for the anchor scrapings of the stipes of Pterygophora, research conducted on wounding, healing and survivorship of Pterygophora californica, Eisenia arbrea and Laminaria setchellii conclude that there should not be reason for concern. Biochemical studies have characterized the stipes of these kelps as having a high modulus of elasticity, capable of remaining upright when out of the water, but still flexible enough to be bend and return to their original shape without being damaged. The Pterygophora californica will bend in excess of 360 degrees without breaking, as noted by DeWreed et. al. (1992). Therefore, anchor and chain disturbance and concern for breakage should not be of concern in that cracks seem unlikely to arise from bending. Furthermore, considering these kelps survive high wave forces, abrasions on rocks and barnacles, as well as urchin grazing, cuts and nicks of greater then 0.2 mm are common occurrences in these kelp stipes, according to DeWreed et. al. (1992). In their research study, they razor cut and filed stipes of all 3 species mentioned above, and found that over time the volume of tissue had re-grown significantly. While tissue re-growth did not significantly increase mean strength of the stipes of all three species, the newly cut stipes of P. californica exhibited a significant 65% increase in strength.  Neither razor cuts nor file cuts significantly decreased the survivorship for P. californica.
 The anchor arm and the anchor chain were noted laying on and rolling over patches of strawberry anemones. However, during dive number three at Lobos Rocks, the anchor had free fallen from its initial setting at 45 feet to 60 feet, and after studying its former position, no adverse impact was noted to the strawberry anemones on the rocky wall where the anchor had being resting. No adverse impact was noted on the strawberry anemones on which the anchor rolled over. No side way scraping by the chain was ever detected, only a length wise scraping when the anchor chain was slacked. Even then, the scraping was limited to the small area at the highest point on the rocky surface. The one concern which arises regarding anemones, is the incident with the White Spotted Rose Anemones. After falling from 45 feet to 60 feet, the tip of one of the anchor wings rested on a White Spotted Rose Anemone, partially pinning it to the rocky surface. No cuts or  lacerations were conspicuous, but what resulted upon the lifting of the anchor is not know.
 The next item of concern relates to the anchor scraping the rocky surface, riping off Fleshy Red Kelp, Articulated Coralline Algae, and leaving an open scar on the rock. This could be considered significant impact, but according to studies of the California temperate waters and else where, this may not be adverse impact. In a study of disturbance in marine intertidal boulder fields, Sousa (1979) describes the major forms of disturbance which occurs due to waves and winter storms overturning small to large boulders. This opened up space, interrupting the successional sequence and determining the local levels of species diversity. He found that the frequency of disturbance determined the degree of between-boulder variation in species composition and diversity. Smaller boulder which are frequently turned, sample the available pool of spores and larvae more often. As a result, a great number of different species occur as single dominants on these boulders. Species diversity was low on most large boulders since the disturbance of these substrata is long, there is little available space for colonization. The species which becomes established first inhibits the recruitment and growth of subsequent colonist.
 In further consideration of the scraping of the rocky substrate by the anchor, consider a similar study by Dayton (1991). He studies physical variables, such as wave exposure, and battering by drift logs, as having important effects on the distribution and abundance of many of the sessile species on the intertidal community. They have an effects in the provision of free space as wave shocks enlarge patches created by log damage. Grazing by Pisasters, limpets, and gastropods can also create small clearings which after enlarged by wave action,  are impossible to differentiate  from free space due to log damage, according to Dayton (1971).
 
 During the lifting of the anchor at the Pinnacle of Tremendous Proportion, a large chunk of white crustose coralline algae is witnessed torn from underneath  red fleshy algae turf. Crustose coralline algae are slow growing calcareous plants, with a hard surface suitable for the attachment of the faster growing fleshy algae, and abundant in the subtidal. Experimental studies have indicated that in the absence of grazers to remove fleshy macroalgal epiphytes from crust surfaces, crustose corallines become overgrown and eventually die. This dead coralline must be removed to allow the recruitment of fleshy red algal. However, Johnson and Mann (1985) suggest that when herbivores are absent, coralline algae may exert a significant effect on the structure of seaweed assemblage by inhibiting algal recruitment. They believe that the mechanism for this antifouling effect may be sloughing of epithallial cells from the surface of the crust. Since Coralline algae are adapted to low light levels, and apparently thrive beneath dense canopies and turfs, there is no case for a general application of the "grazer-dependent" hypothesis for the maintenance of coralline crusts. In their study they found that fewer plants grew on the crusts than on the bare granite. It would appear that the reaping and tearing of the coralline algae by the anchor would not be a concern, considering the abundance and recruiting factor of coralline algae and its inhibiting of the fleshy red algal recruitment.
 Sea-urchin mediated deforestations have occurred, not only in Macrocystis forests, but also in Laminaria forest world-wide. In January 1986, a sea-urchin mediated deforestation began at the outer Pinnacles in Carmel Bay, California, USA. In kelp forests, sea urchins normally subsist on unattached drift algae. If this food source is reduced, sea urchins may abandon their normally sedentary habits and search actively for food concentrating on previously untouched attached plants. Purple and red sea-urchins at the pinnacles ate and removed nearly all erect plants, leaving only encrusting coralline algae. By October 1986, nearly all non-crustose algae had been removed, as were most sessile invertebrates according to Watanabe and Harrold (1991. This serves as a prime example of the theory that communities and the populations which comprise them are in a state of local disequilibrium. Andrewartha and Birch (1954) argue that environmental heterogeneity reduces the chances of extinction. When some local populations are increasing in size, others are declining towards extinction, and still others may remain relatively stable.
According to Sousa (1979), each local population is likely to go extinct in time, but in the absence of any large enviromental changes, surviving populatons serve as sources of propagules for recolonization of the vacated favorable sites. Species with similar resource requirements coexist locally not because of evolved differences in their use of resources, but as a consequence of disequilibrium conditions and renewed space generated by disturbances. The length of time that these species coexist depends upon the frequency and intensity with which disturbances occur in the particular area, the relative rates of recruitment of the species in question, and relative susceptibility of the species to various sources of mortality. If the time between disturbances is long, a single species may dominate and others will go extinct locally. The later species persist globally in the system of patches by colonizing other patches in which conditions are more open according to Souza (1979). For these reasons and the points stated previously, it would appear that the small scrapes caused by anchor and chain disturbances cannot be seen as adverse impact, but simply as another physical disturbance contributing open space for the continual recruitment of competitive species within the kelp community.
 The remaining issue on the list of disturbances is the anchor landing close to a fluted bryozoan and a hydrocoral. Bryozoans (Hippodiplosia insculpta) are brittle and presumably easily broken in the unlikely event they are impacted by an anchor or chain. According to some research which has been done on the growth rate on bryozoan, the Fluted bryozoan (Hippodiplosia insculpta) may reach 4 inches in height  by 5 inches in width, and the Nothern Staghorn bryozoan (Heteropora magna) may reach 4.5 inches in height by 6.5 inches in width. It is believed that Lacy bryozoan (Phidolopora pacifica) grows at a rate of 3 centimeters within six weeks, and may reach 4 inches in height and 8 inches in width. Webster (5-9-00 personal communication) in an unpublished study, found that encrusting bryozoan covered the open space of a removed seven inch abalone within six weeks. Encrusting bryozoan, is commonly used as a prerequisite foundation for various algal growth, according to Webster (5-9-00). Bryozoans are filter feeders and found in areas of high currents. Stagehorn bryozoan are responsible for clogging up the intake tubes pumping 2000 gpm of water to the Monterey Bay Aquarium exhibit tanks. Bryozoans are considered "weedy" and are often the first colonizers of their substrate. However, medical research is
 currently on going in relationship to certain properties contained within bryozoan which may be helpful in the cure of cancer. In regards to anchor disturbance of bryozoan, it appears that a direct anchor landing on any bryozoan would have a specific negative impact per unit. However, as a whole, considering its growth rate and abundance, this unlikely disturbance can be considered insignificant.
 California hydrocoral (Stylaster california) would suffer adverse impact should it come in contact with a boat anchor or chain. While their growth rate is not known, it is believed that the life span is several decades and their growth rate is less than 1 cm per year, but it may take 20 or more years for hydrocoral to grow 10 inches. They can be found outside the Monterey Bay, exposed to high water energy from waves or currents. It may not grow in the Monterey Bay proper due to a higher degree of sediment flow into the bay. Hydrocoral may not like the sediment in the Bay during its early growth, according to Webster (5-10-00 personal communication). Most hydrocorals live in deeper water (> 100 m), but a few live in shallow water, usually on rocky surfaces, in crevices, under overhangs, on walls and rocky outcrops frequented by divers. They are common at the Outer Pinnacles, at Yankee Point, at Point Joe, and other dive sites past Point Lobos.
During the establishment of the Monterey Bay Aquarium, attempts to acquire hydrocoral from the Pinnacles in Carmel, and to grow it on artificial rock failed. Hydrocoral recover slowly, since recruitment by larvae probably has limited dispersal. They have brooded larvae and most seem to settle near their mother, according to Potts (5-19-00 personal communication). The colonies are fragile and easily broken. They are vulnerable to attack by boring organisms. While there are no specific studies on hydocorals, they would be sensitive to the same disturbances that affect scleractinian corals. Cumulative human impacts could be expected to cause local degradation from diver's fins, chain whiplash and anchor contact. Of all the previously stated anchor and chain disturbances, impact to hydrocoral could be adverse and significant to each Stylaster california contacted. However, during the total of  seven dives conducted for this study, only one hydrocoral was spotted and photographed, and this was at Que Paso Pinnacles at a depth of seventy feet. Despite localized distributions in California, Potts (5-19-00) suspects Stylaster california are not threatened by direct human activity, simply because they tend to live on exposed rocky coastlines that people avoid.
This study did not include research on the affects of anchoring on sandy bottom. It is believed that a lot of study has been done on this particular subject where it pertains to Tropical sandy and muddy bottoms.  Nevertheless, Potts (5-19-00 personal communication) suggests that repeated anchoring causes local degradation, homogenization, and reductions of diversity on sandy or muddy bottoms. If moorings were to be considered for installation, this study would have to be expanded to include a study of anchoring and mooring disturbance in these local sandy bottoms.
 

Discussion

If a test mooring was to be placed, where should it be, and what are the characterizations of that dive site?

 A characterization was done of Eric’s Pinnacle  to determine if it would be a good study site for a test mooring. The location of Eric’s Pinnacle is at  Universal Tranverse Mercater (UTM) of 4054818N 596704E UTM, Zone 10, Datum WGS 1984. Eric's Pinnacle can also be located with GPS readings of 36°38.048'N  121°55.040'W (NAD 27),  36°38.044'N  121°55.102'W (NAD 83). The sonar mapping of Eric’s shows that it has an approximate radius of 20 meters, comes up from a maximum floor depth of 61 feet at its deepest, to 19 feet from the surface. Two additional huge boulders rest to the South East of it and several other smaller boulders lay to the West of Eric’s. A sandy area is directly East of the pinnacle, and most knowledgeable dive boats operators drop their anchor in that sandy area.  The predominate marine life consists of brown kelp, red leafy kelp, strawberry anemones, and bryozoans, among other invertebrates. However, no hydrocoral was sighted, nor believed to exist at this site, or anywhere within Monterey Bay proper So, there should be no concern of adverse impact to hydrocoral. Eric’s Pinnacle is between the two popular dive sites of Chase Reef and Lover’s Point. It is reasonable to suspect that a surface mooring at Eric’s would be visible from land, and by passing boaters. Therefore, it is reasonable to speculate that a mooring at Eric’s would invite increase traffic to that dive site.
 
Visitors would increase the pressure presently felt by Eric’s by bringing in more divers, fishermen, spearfishing, scientist, and further collection from many of the aquariums from Central California, according to Cooper (5-24-00 personal communication). Cooper suggest that Eric’s Pinnacle is too small of an area, and the fish and invertebrate life would soon be decimated, unless the area was protected and declared a "no take" zone. In addition, Cooper (5-24-00) stated that the length of chain needed to mark the site, due to sea conditions,  tidal and current changes, and swells, would be so long, that the chain itself would play havoc with the benthic life one is  trying to protect. In addition, to be effective, the moorings would have to be in a marine protected area. Webster (5-9-00 personal communication) stated that the Monterey Bay Aquarium spreads its collecting out over a large area
outside the Ed Ricketts Underwater Park. In order to make Eric’s Pinnacle a refuge, Webster states that it would have to be considered in the context of the state's review of all protected areas state-wide. If all interested local parties were to unanimously request the California Department of Fish and Game that Eric’s Pinnacle be declared a "no take zone" a buffer might be created around Eric’s Pinnacle.

A more detailed study of Eric’s would have to be performed prior to the installation of a testing mooring. This study could be used to compare with a subsequent study after the mooring test period was terminated. BayNet, Boat Charters, and others could be used to do a comparative count of visitations prior to the installation and after the removal of the mooring. The adjacent Pinnacles, Aumentos, could be used to do a comparative study, as a pinnacle without a mooring.
 Several Governmental bodies would need to give approval for the installation of moorings. The Monterey Bay National Marine Sanctuary (MBNMS) has already visited this issue before, and according to Cooper (5-24-00) the Sanctuary was less then enthusiastic. MBNMS’s Permits and Enforcement Coordinator, Kathey (5-8-00 personal communication) has not ruled out a testing mooring, but suggested the Sanctuary would probably need a competent scientific study justifying the need for anchor moorings before proceeding with any permits. According to Cooper (5-24-00) at least 58 mooring would have to be place at Chase Reef alone. A percentage of them would be surface visible and the remaining would be submerged to give each dive site a respite from over use. However, Cooper doubts that the City’s of Monterey, Pacific Grove and Carmel would allow visible mooring buoys and would consider them eye sores for the tourist industry. The alternative is to have submerge buoys as in the Tropics, but Central California does not have Tropical water visibility and searching for submerged buoys in these water would be an unworkable setup.
Either way, the U.S. Coast Guard considers buoys to be a navigational hazard, and they too have resisted the installation of moorings in Monterey Bay. The Coast Guard would enforce ownership maintenance of the moorings and they would do routine inspections of the moorings and charge the proprietors of these private mooring for Coast Guard inspection cost.
Liability would become a factor. Should an accident occur, a boat going a ground due to the failure of a mooring, who would be liable? Would charter boat owners pay for the mooring, or would divers self tax? Each mooring, like in the Caribbean, costs $1500 a year just to maintain, multiplied by the number of buoys required in the system, makes it an expensive proposition. At present there are not enough divers to justify the expense of a mooring, and neither divers, nor charter boat owners can afford the cost of mooring maintenance. Even if grants were received from agencies and foundations, who would be the responsible party? Would they be able to enforce  private  use in a National Sanctuary? The California Coastal Commission and the California  State Lands Commission for MOA's would have to grant permission for the placement of moorings. The City of Pacific Grove has property jurisdiction out to 60 foot depth due to a submerged land grant to the City in 1936. Since Eric’s Pinnacle is within 60 foot depth Pacific Grove could veto a plan they may consider an eye sour. Moorings are not a workable solution, according to Doreck (5-25-00 personal communication). What do you do if the moorings are full? Are dive boats not allow to anchor? Would the commercial dive boats be held responsible for maintenance of moorings, Doreck (5-25-00)? Clayton (5-25-00 personal communication) suggests that the solution to anchor disturbance is not moorings, but better boater education, to be sure the anchors is dropped on sand. He states that in the southern coast dive sites, where the bottom is mostly rocky, boaters presently use a BRUCE anchors, which is the least disruptive to the bottom.
 

What are the logistics of placing a mooring?

 A great deal of reacher has been done on moorings, and these resources are readily available. Massive information is available via the internet on moorings in Florida, Grand Cayman, Bonaire, Hawaii and here in the City of Monterey. There is a publication available from NOAA called Mooring Systems, and that should be available from the MBNMS. PADI, Project Aware, has a publication titled, Mooring Buoy Planning Guide, which is full or resources. According to Webster (5-9-00 personal communication) MBARI, out of Moss Landing, uses railroad train wheels for the base of their moorings. Webster believes that the director of technical support at MBARI might be willing to loan out a train wheel for a testing mooring. Also, Webster stated that in order to land such a heavy object, that a boat vessel with an A frame would be required. Moss Landing Marine Laboratories has the John Martin Research Vessel which is equipped with the necessary structure. If a base as heavy as a train wheel was to be used, the same vessel and equipment would be required to retrieve the mooring base, after the testing period, and the MBNMS would require its removal.

Conclusion

This has been a limited and abbreviated  study of anchor disturbance from diving boats in the Monterey Bay area. In light of the above analysis and discussion, one would be hard pressed to recommend placement of permanent moorings, the placement of a testing mooring, or the continued study of any boat anchoring disturbance in the pursuit of a mooring project in the near future. One can not justify the placement of moorings, which in turn concentrate boats to very specific impact areas. The system presently in use by dive boats, allows them to roam the general dive vicinity, thus diffusing any potential anchor and diver disturbance within those dive areas, which otherwise would be concentrated by the use of moorings. Any impact that may now be occurring with the present anchoring system, appears to be insignificant. In fact, this present anchoring system may, by giving these areas sufficient recovery time, be stimulating greater diversity of species recruitment within those areas of anchor disturbance. Due to the limited disturbance and impact noted in the analysis of this study, and the potential for adverse reverberations from placing moorings, as outlined in the discussion section above, one must conclude that no additional action need be taken to mitigate boat anchor disturbance.
 
 

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