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s Environmental Issues Associated with Beach Nourishment This chapter addresses the major environmental issues associated with beach nourishment. It considers both beneficial and detrimental effects and notes where adequate research has not yet taken place. Suggestions for appropriate research are considered. Beach nourishment operations can disrupt the existing biological communi- ties in subaerial zones of beaches and in the borrow sites where dredging occurs. Effects have also been observed in the shallow subtidal habitats adjacent to some nourished beaches. Naqvi and Pullen (1982), W. G. Nelson (1985), Goldberg (1989), and Grober (1992) have reviewed studies of the ecological effects of beach nourishment. The effects can be quite varied, ranging from short- to long- term alterations and including both detrimental and beneficial effects. Several reviewers have also noted that there has been little standardization in the design of environmental monitoring studies and that most of the studies conducted to date have been limited in duration or scope. As a result, many of the environmen- tal concerns regarding beach nourishment remain unresolved. Technical and sci- entific knowledge is incomplete, especially with respect to the indirect effects on biota that use the habitats affected by nourishment operations. SUBAERIAL BEACH HABITATS The subaerial beach can be divided into two major zones. The uppermost zone is the supralittoral (dry) portion of the beach that lies landward of mean high water and may extend into the primary dune system. On eroded beaches requiring replenishment, the upper extent of this zone may terminate at a seawall, rock 107
108 BEACH NOURISHMENT AND PROTECTION revetment, or other hard structure associated with coastal development. The in- tertidal zone, located between mean high water and mean low water, forms the second distinct zone of the subaerial beach. The width and characteristics of this zone can vary considerably, depending on tidal range, sediment size, and wave energy. Because one of the primary purposes of beach nourishment is to restore eroded portions of the subaerial beach, most of the fill material is placed in the supralittoral and intertidal zones. However, burial of shallow subaqueous habitats also occurs as the beach is widened. This mimics naturally occurring rapid burial events associated with berm or beach cusp formation except that it occurs on broader spatial scales and may involve greater changes in sediment loads. Physi- cal changes to the beach environment vary during and after nourishment, depend- ing on the source and type of sand used. Most projects attempt to use sandy material that is comparable in composition and grain size to the existing beach. Sand sources with a high silt/clay content are generally avoided, although some nourishment projects have used material with a relatively high percentage of these fine-grained materials (e.g., Reilly and Bellis, 1978~. In addition to its not being particularly suitable as beach fill material, dredging sand deposits with a high percentage of fines can have adverse effects on existing biota in adjacent habitats as a result of increased turbidity and sedimentation. Several studies have shown that even when beach-compatible materials are used, the nourished beach may be physically altered compared to nonnourished beaches with respect to sand compaction, shear resistance, moisture content, grain size and shape, and other factors (Nelson and Dickerson, 1988; Ackerman et al., 1991, 1992; Grober, 19921. The slope of the beach in the intertidal zone is also generally steeper after nourishment until the beach reaches a more stable profile, and there is often a distinct scarp that forms in this zone as the beach fill adjusts. The height of this scarp can vary from a few centimeters to more than a meter (Nelson et al., 1987; Reilly, 1979~. However, it should be noted that scarps also occur on beaches that have not been nourished. The obvious benefits of a nourishment project include improved protection of coastal properties from wave damage and improvement of the beach for recre- ational activities. Beach nourishment projects are generally not done to protect undeveloped upland habitats or to restore the beach for indigenous biota or biota that use the beach for foraging or nesting, although this benefit has been cited occasionally. Potential negative consequences of beach nourishment include: . disturbance of the indigenous biota inhabiting the subaerial habitats, which may in turn affect the foraging patterns of the species that feed on those organisms and · disruption to species that use subaerial beach habitats or adjacent areas for nesting, nursing, and breeding.
ENVIRONMENTAL ISSUES ASSOCIATED WITH BEACH NOURISHMENT 109 The ecological consequences of beach nourishment on subaerial habitats have not been well studied, even though several hundred nourishment operations have been completed along the coastline of the United States alone. The indigenous fauna of a sandy beach are primarily burrowing species that are well adapted to this constantly changing and relatively stressful environment. In the upper beach zone, dominant fauna generally include talitrid and haustoriid amphipod species and crabs of the genus Ocypode (ghost crabs) in more southern latitudes (Dahl, 1952; Trevallion et al., 1970; Shelton and Robertson, 1981; Williams, 1984~. Macrofauna typically found in the intertidal zone include haustoriid amphipods, polychaetes, isopods, mollusks, and some larger crusta- cean species such as mole crabs (Emerita spp.) and burrowing shrimp (Callianassa spp.J in the lower intertidal and swash zones (Dexter, 1972; Croker et al., 1975; Shelton and Robertson, 1981; Knott et al., 1983; Williams, 1984~. Both the abundance and diversity of these organisms are higher in the lower intertidal zone and can vary seasonally, especially in more temperate latitudes. W. G. Nelson (1985) provides an excellent review of the distribution and life history patterns of dominant beach fauna typically found along the U.-S. Atlantic and Gulf coasts. Parr et al. (1978) describe similar patterns for a beach on the Pacific coast. When a beach is nourished, large volumes of sand are placed within the supralittoral and intertidal zones. The amount of sand overburden varies across the width of the beach, but the greatest volume of material is generally placed along the upper extent of the beach where biological diversity is lowest. Sand flowing onto the lower portions of the beach during the nourishment operation can increase the beach height in the intertidal zone from several centimeters to more than a meter. Organisms living in the sands of the nourished beach will be smothered unless they are able to leave the area or burrow up through the sand overburden. Among the infaunal organisms typically found on a sandy beach, only the larger, more mobile organisms such as the ghost crab are likely to be able to avoid smothering by leaving the area. Reilly and Bellis (1978) observed a decrease in the density of ghost crabs following a nourishment project at Bogue Beach, North Carolina, and suggested that the crabs may have moved away from the nourished area in response to the physical disruption or loss of suitable food resources. Their study did not identify the period required for the ghost crab populations to recover, and other researchers have not attempted to monitor these decapod popu- lations. Only two documented projects have examined the burrowing abilities of intertidal and/or subtidal sand-dwelling species following burial by sand overbur- dens (Maurer et al., 1978, 1981a, b, 1982, 1986; W. G. Nelson, 1985~. Maurer and his colleagues examined seven species commonly found in nearshore subtidal environments and found that some of the organisms were able to burrow up through sand overburdens of up to 40 cm, although survival depended on sedi
0 BEACH NOURISHMENT AND PROTECTION ment composition and temperature. W. G. Nelson (1985) also noted that the three species tested could deal with instantaneous burial at depths of up to 10 cm, although some mortality occurred, depending on grain-size characteristics. No studies have been published on the effects of burying sand-dwelling benthos with sediment overburdens of a meter or more, which may occur during nourishment. Lynch (1994) evaluated this issue for several infaunal species typically found on southeastern beaches and found that many of the species can migrate through large overburdens of sediment in the range of 0.6 to 1 m. The temporary loss of infaunal communities through sand burial is expected and largely unavoidable during beach nourishment operations. The more impor- tant issue is the recovery rate of these communities following completion of the project. Only a few studies have evaluated the changes occurring among infaunal assemblages of subaerial beach habitats following nourishment. Table 5-2 lists the studies considered in this review. Most of them have documented only tempo- rary alterations in the abundance, diversity, and species composition of the inter- tidal fauna following nourishment, ranging in duration from a few weeks to a few months. However, sampling efforts for many of these studies were limited with respect to the number of samples collected at a given site or the duration and frequency of sampling. The studies have also been limited to areas south of 36° N latitude on both coasts. Thus, although past monitoring projects indicate that infaunal communities in intertidal portions of the beach recover fairly rapidly, additional studies are warranted to evaluate recovery rates more fully in regions where extensive intertidal habitats exist and where studies either have not been conducted or the data are too limited to assess recovery rates adequately. The indirect effects of temporary losses or alterations in the benthos on the foraging activities of marine and avian predators should also be considered in these studies. Loss of preferred food resources for marine predators may be less critical in the intertidal zone than in subtidal habitats, but many shore bird species actively feed in the intertidal zone and may be adversely affected by nourishment operations. To date, no studies have been published on the effects of beach nourishment on shore bird foraging patterns. The effects of beach nourishment on the nesting success of threatened or endangered sea turtle species is another major concern related to beach nourish- ment projects completed in southern regions of the United States. The threatened loggerhead turtle (Caretta caretta) is commonly found nesting on southern beaches, and leatherback (Dermochelys imbricata) and green (Chelonia mydas) turtles are known to nest in this region as well. The turtle nesting season generally extends from the spring through late summer, although there is some variability in the initiation and completion of nesting activities, depending on location within the region (Dodd, 19881. Sea turtles emerge from the ocean at night, lay their eggs in a nest cavity in the supralittoral zone, and return to the ocean. Nourished beaches can restore or provide suitable nesting habitat for sea turtles, resulting in an increased number of nests on several beaches where nest densities have been
ENVIRONMENTAL ISSUES ASSOCIATED WITH BEACH NOURISHMENT TABLE 5-1 Beach Nourishment and Beach Disposal Projects Considered Beneficial to Biota Using the Beach or Adjacent Upland Areas 111 Location Resource Benefited Reference Boca Raton, FL Miami Beach, FL Jupiter Island, FL Captiva Island, FL South Seas Plantation, FL Pompano Beach/ Lauderdale-by-the-Sea. FL Boca Raton, FL, and John V. Lloyd Beach, FL Cape Cod, MA Brown pelicans and other shore Unpublished data, P. Wilkinson, birds (protection of nesting South Carolina Wildlife and habitat from erosion) Marine Resources Department Threatened or endangered Spadoni ( 1993) plant species (protection from loss through erosion) Loggerhead turtles (improvement of turtle nesting habitat and/or nesting sources) Piping plovers (increase in available nesting habitat) LeBuff and Haverfield (1990)7 Flynn (1992), Spadoni and Cummings (1992); and Witham (1990) Melvin et al. (1992) monitored (see Table 5-1~. However, some physical aspects of the nourished beach can influence the viability of turtle nests and nesting activities, and propos- als to conduct nourishment projects during the turtle nesting season have gener- ated considerable debate, particularly in Florida. There are several known effects that active nourishment operations can have on sea turtles during the nesting season. Pipelines placed on the beach can create a barrier that prevents females from reaching suitable nesting sites. Artificial lights, noise, and the increase in human activities during these projects may also deter nesting females. Many of these problems can be minimized through light- ing restrictions and by limits on bulldozer activity during the night. If a nest relocation project is needed, concerns have been raised that the movement of eggs may result in decreased hatching success, altered sex ratios, decreased hatchling fitness, and interference with imprinting mechanisms. The success of nest relocation programs has been monitored on several beaches in Florida (Spadoni and Cummings, 1992; Higgins, 1993~. The results indicate that hatch- ing success of relocated nests is not significantly different on nourished versus nonnourished beaches. However, more work is needed to resolve all the issues associated with these programs. Concerns related to active beach nourishment operations are obviously less important on beaches that have eroded to a point at which successful turtle nesting is not possible or does not normally occur. In other situations, natural resource agencies at both the state and federal levels may deny a permit request for beach nourishment or place special permit conditions on the project to minimize adverse effects on sea turtles.
2 BEACH NOURISHMENT AND PROTECTION Even after the nourishment operation has been completed, physical charac- teristics of the beach may affect turtle nesting success. As noted previously, nourished beaches often form scarps in the intertidal zone that can result in an increased number of false crawls. Alterations in the compaction, density, shear resistance, color, moisture content, and gas exchange of the beach sands can also influence the incubating environment of a nest, in turn affecting hatching success and hatchling sex ratios (Nelson and Dickerson, 1988; D. A. Nelson, 1991; Ackerman, 1991; Ackerman et al., 1991, 1992~. Some of the physical changes that adversely affect nesting success can be dealt with as part of the construction plan. For example, the negative effects of sand compaction and scarp formation can be reduced or eliminated through mechanical tilling and grading of the beach. Other factors that may affect the suitability of the beach as an incubating environ- ment may be more difficult to resolve, but it should be noted that several monitor- ing programs have documented no significant difference in hatching and emer- gence success of turtles on nourished versus nonnourished beaches (Raymond, 1984; Nelson et al., 1987; LeBuff and Haverfield, 1990; Steinitz, 1990; Ryder, 1992J. One study (Broadwell, 1991) even documented greater hatching emer- gence success and hatchling weights for a nourished beach in Boca Raton com- pared to an adjacent natural beach. The results of these studies suggest that nourished beaches can provide a suitable habitat for turtle nesting, but more research is needed to resolve all the problems of this complex issue. Concerns have also been raised regarding the effects of beach nourishment on threatened or endangered bird and plant species. For example, the piping plover (Charadrius melodus) is listed as an endangered (Great Lakes watershed only) and threatened species by the U.S. Fish and Wildlife Service (USFWS) (1993~. This species nests on beaches above the high tide line during the spring and summer. Melvin et al. (1991) noted that beach nourishment can improve the quality and availability of plover habitat by creating substrate that is higher, wider, and less vegetated compared to an eroded beach. However, they noted that nourishment may adversely affect breeding plovers if the dredged material is not a suitable nesting substrate or if deposition of the material occurs at a time and place that disturb nesting plovers. The U.S. Fish and Wildlife Service recently placed the seabeach amaranth (Amaranthus pumilus) on its list of threatened plant species. Beach nourishment projects completed where this species is present will need to incorporate measures to protect these plants from adverse effects related to construction activities, but the USFWS does note that nourishment can have a positive impact on this species (Federal Register, 1993~. SUBTIDAL BEACH HABITATS Bottom habitats in the nearshore surf zone immediately adjacent to a beach often support a diverse array of biota that may be directly or indirectly affected by beach nourishment operations. These biota include benthic invertebrate assem
ENVIRONMENTAL ISSUES ASSOCIATED WITH BEACH NOURISHMENT 113 blages inhabiting the sandy substrata, epifaunal invertebrate and macrophyte assemblages that form reef communities on hard substrata, and the fish and motile crustacean assemblages that reside in or forage on these habitats. Infaunal macroinvertebrate communities typically found in the nearshore surf zone and deeper subtidal sand-bottom habitats include polychaetes, amphi- pods, isopods, decapods, polychaetes, mollusks, echinoderms, and a variety of other taxa (Marsh et al., 1980; Knott et al., 1983; Gorzelany and Nelson, 1987; Rackocinski et al., 1991, 1992; Van Dolah et al., 1992; Deis et al., 1992J. Many of the dominant infaunal species found in the surf zone are the same as those inhabiting the lower intertidal zone, but the diversity and abundance of these fauna are generally much higher in the subtidal zone. Many other epibenthic invertebrate and finfish species are found in the nearshore sand-bottom habitat, and in some areas, these resources are commercially important. For example, the nearshore zone along the southeastern and Gulf coast states supports large popu- lations of penaeid shrimp species, which represent a major part of the commercial fisheries harvest for those states. Hard-bottom reef habitats are most commonly found along the Florida coastline (W. G. Nelson, 1989, 1990; Goldberg, 1989), although extensive nearshore reefs have been documented in South Carolina (Van Dolah and Knott, 1984J. The dominant sessile biota in these habitats in- clude sponges, octocorals, hard corals, hydrozoans, bryozoans, ascideans, and attached macroalgae. These taxa, in turn, support a diverse assemblage of motile epibenthic invertebrate and finfish species, including many that are commercially important. In general, the diversity of species found in reef habitats is much greater than that observed on sand-bottom habitats (Knott et al., 1983; Jaap, 1984; W.G. Nelson, 1985; Coastal Planning and Engineering, 1992~. Beach nourishment may affect adjacent sand-bottom and hard-bottom habi- tats, both physically and biologically. Physical alterations may include: · burial of bottom habitats in the surf zone as the beach is widened; · increased sedimentation in areas seaward of the surf zone as the fill mate- rial redistributes to a more stable profile; changes in the nearshore bathymetry and associated changes in wave action; and · elevated turbidity levels, particularly in the vicinity of the pipeline efflu- ent. . The movement of sediments away from the nourished beach can have both beneficial and detrimental effects. Down-current drift of coarser sediments may benefit beaches adjacent to the nourishment project by providing additional sand material. However, this drift may accelerate the filling of navigation channels in down-current areas, which could increase the frequency of dredging required to maintain the channel. Increased sedimentation in areas seaward of the surf zone may also occur as the fill material redistributes to a more stable profile. In most
4 BEACH NOURISHMENT AND PROTECTION situations the accumulation of sandy material in the nearshore zone may be gradual and will not result in a major change in sediment composition. However, when there is a relatively high percentage of silts and clays in the fill material, the composition of sediments may be temporarily altered in the nearshore zone. Few studies document the alongshore movements of sand beyond the limits of most nourishment projects. Biological effects resulting from physical alterations in the nearshore zone are not well documented. Motile invertebrates and fishes typically found in this zone should be able to avoid most of the direct effects of beach nourishment, although larval forms found in the surf zone could be adversely affected by high turbidity levels if they occur. Two surveys of fish populations conducted in Florida before and after beach nourishment showed no evidence of adverse ef- fects to the composition and abundance of the fishes sampled (Holland et al., 1980; Nelson and Collins, 1987~. Quantitative assessments of the effects of beach nourishment on crustacean populations, such as penaeid shrimps, have not been conducted, but these species are often found in turbid waters. The extent and biological effects of turbidity plumes resulting from beach nourishment operations are not well understood. The state of Florida currently restricts the levels of turbidity that can occur outside a predetermined mixing zone to 29 NTUs (nephelometric turbidity units) above corresponding back- ground samples, but this limit is not based on any published studies that would provide a clear biological rationale (Goldberg, 1989~. Within the mixing zone, which has specified dimensions, turbidity is not limited. Other states generally do not have restrictions on the turbidity levels resulting from pipeline effluents, which can be high in the immediate vicinity of the outfall. For example, Van Dolah et al. (1992, conducted a limited survey of turbidity levels near the pipe- line outfall of a nourishment operation at Hilton Head Island, South Carolina, and observed turbidities that were approximately 50 to 150 NTUs above background levels in an area extending approximately 200 m from the outfall. These back- ground levels were determined under calm conditions and do not represent the maximum naturally occurring turbidity levels, which can be very high during major storms or other disturbances. Biological resources that may be most adversely affected by elevated turbidities include many of the sessile species typically found in hard-bottom reef habitats or seagrass beds. High turbidities and silt loads can smother these organ- isms, inhibit filter-feeding processes, or significantly decrease photosynthetic activity, potentially resulting in long-term damage to these resources (Courtenay et al., 1974, 1980; Goldberg, 19893. Even where turbidity levels are low, nearshore reef habitats that lie within the depth of closure may be destroyed by sand burial resulting from the redistribution of beach fill material. Considerably more data are needed to evaluate the sensitivity of nearshore reef biota to high turbidity levels and changes in sediment overburdens. The direct effects of beach nourishment operations on nearshore soft bottom
ENVIRONMENTAL ISSUES ASSOCIATED WITH BEACH NOURISHMENT 115 communities have been evaluated by a few investigators. Table 5-2 lists the studies considered in this review. In general, these studies documented only limited or short-term alterations in the abundance, diversity, and species compo- sition of nearshore infaunal communities sampled off new beaches. However, several of these studies had inadequate sampling designs that may have precluded detection of significant alterations in the population or community parameters measured (W. G. Nelson, 1991, 1993~. Thus, although it appears that detrimental effects to the nearshore soft-bottom communities adjacent to a nourished beach may be limited, additional studies are warranted, particularly in areas where these resources have not been monitored. In addition to evaluating changes in the general community parameters and species composition of the benthic and dem- ersal resources in these habitats, efforts should be directed toward obtaining a better understanding of functional changes in the trophic contribution of benthic assemblages to the fish and crustacean species that rely on the benthos as a major food resource. BORROW SOURCE AREAS There are many environmental issues related to the sites used for the source of sand material for beach nourishment projects. Potential source areas include sand deposits in upland areas; deposits in estuarine, lagoonal, or inlet systems behind the front beach; sandy shoals in channels that may be dredged for naviga- tional purposes; and sand deposits in nearshore areas within the operational depths of dredging. Mining sand deposits from upland areas can reduce project costs if an ad- equate source of sand near the projects can be transported by truck (Kane, 1990), and assessment of the impacts resulting from the mining operation is much sim- pler. However, upland areas with sufficient sand resources are often not near the beach nourishment site, and the quality of the fill material may be unsuitable for placement on the beach. Nourishing the beach by a trucking operation also can have substantial secondary impacts resulting from transporting the sand, such as damage to road systems and disruption of traffic and beach recreation. Dredging sands from inshore estuarine or inlet deposits may represent an- other relatively low cost method of obtaining fill material, but permits to dredge these areas are often difficult to acquire because estuarine habitats serve as im- portant nursery areas for many marine species. The quality of sand deposits in these areas is also often lower owing to an increased percentage of fines that are commonly present. When suitable sediments are available, inshore areas offer the opportunity to conduct dredging operations in relatively protected waters. This situation can reduce downtime owing to bad weather, particularly if dredging must be done during the winter months. Dredging in inland waters and inlets may also serve a dual purpose if it is tied to the maintenance of navigational channels. Sand deposits located in nearshore ocean habitats are the most common
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8 BEACH NOURISHMENT AND PROTECTION source of beach fill material. Possible sources include low-tide bars or accreting beaches, ebb-tide deltas around inlets, and offshore sand deposits. Offshore de- posits provide as much as 95 percent of the sand for beach nourishment projects at this time. Sediment composition in these areas is often nearly compatible with the beach to be nourished, but costs may be greater if the borrow site is not located near the project area or if downtime is increased owing to sea conditions in which dredging operations are unworkable. The long-term physical alterations resulting from the dredging of sand bor- row sites in estuarine and marine habitats have not been well documented. The borrow areas are often surveyed immediately after dredging to obtain estimates of the volume of material removed, but subsequent monitoring of bottom bathym- etry and sediment composition have been examined in only a few studies (see Table 5-31. The majority of those studies have shown decreases in the mean grain size, including, in some cases, increases in the percentage of silts and clays in the borrow sites following dredging. Data on the refilling rates of borrow pits are especially lacking, but both published and unpublished observations suggest that many borrow areas used in past nourishment projects had not filled in or were filling at a slow rate when they were reexamined (Watts, 1963~. This point has significant environmental implications because long-term renourishment pro- grams may require the use of several borrow areas that will be altered both physically and biologically for extended periods. The physical effects of inshore and offshore borrow areas on surrounding habitats generally have not been evaluated. In estuarine areas, large borrow sites may affect tidal prisms, current flow, and bottom bathymetry in areas surround- ing the site. In nearshore and offshore areas, creation of a borrow pit may affect the stability of ebb-tide shoals or reduce sediment transport to areas down-current of the borrow site. Wave energy and the stability of the beach may also be affected if the borrow site lies within the depth of closure. The primary biological effect of dredging borrow sites is the removal of benthic assemblages inhabiting the surficial sediments. This change may indi- rectly affect other species that use the benthos as a major food source. Dredging activities can also increase turbidity in the vicinity of the borrow area, both during dredging and afterwards if the site accumulates silts and clays (Naqvi and Pullen, 1982; Goldberg, 1989; Grober, 19921. Deep holes may also result in altered water-quality conditions, such as decreased dissolved oxygen levels or increased hydrogen sulfide levels (Murawski, 1969; Saloman, 19743. This prob- lem may be more likely to occur in protected waters that do not have good circulation. Further, dredging operations have been known to damage reef habi- tats in areas adjacent to the borrow area when buffer areas have been inadequate (Grober, 1992~. This latter problem is avoidable, however, by requiring adequate buffer zones and using accurate positioning systems. Recovery of the benthic communities in borrow sites following the dredging operation has been studied in a few areas (see Table 5-3 for a list of studies
119 Cq s~ ~s o z C) Ct m _d U: C~ . Ct ~_ 3 o ._ Ct x Ct ,s V) ._ V) ._ '_1 o ._ o Ct ._ o _4 o ._ Ct Ct ._ C~ 1 .o ,o C) - oc ~o ~ ._ - 5 ~ C)^ ~ P~ V) ~ - ._ o ._ o C) ~ ~ o ~ V .= ~ ~ o ._ ~,, C~ o oo E~ C ~(L) - _ D - ~ ~ D 5 _ ~ ~ D ~ A ~ ~ ~ - 5 5 o - - O O - - O _ - 0 a ~ O~ _ ° D _ _ _ D D ~ b D ~_ _ 5 ~ D _ - - ~ ~D _ _ ~3~'v=~v ~v=~v v~> =~> -} c) a~ ~ :^ £ s~ ~ s~ =, C~ ~ C~ U: Ct C~ Ct C~ _ 1_ $_ _ _ - ~ ........ Ct e~ ~ ~ ~ C~ C~ U: C~ C~ C ~ ~ ~ Ct s ~, C s ~ ._ ~ o C) ~ e~ s ,_ ._ .. V: ~ .. ~ - _ C~ ~ C~ o ._ o ~ ._ ~ P: ~ C~ s ~ ~ C - ._ o _ 50 C) Ct _ s ~ .. V, Ct . . ~ - _ Ct ~ C~ o . _ o ~ _ ~ _ ~t t_ _ ~oo U~ ~ V~ C~ C ~Ct 3 C _ ~ ._ ~._ O - O ._ ~ ~ C) ~ C) e~ 5 _ ~ ~ ·- V: ·- C~ .. Ct o C~ .Q O · U:' O O ~ O P ~ i31 C~ o O ~ ·_ ._ ~ - C~ ._ ,_ '~ _ _ .. e~ - ._ a~ c; ~ ·V: O .= ~ O "a ~ .- Ct ~ c4 ~ O ~00 00 oo 00 X ~ ~a ~G~ _ _ _ _ 1 ~c ~- c~ - c) s ~c~c~ ~c ~ c~ ~ ~' ~ a.> ~=d ~ ~c:~4 ~'~ :- =4 ~- - ~ ~ ~ ~ ~. - . - ~. - Ct . - . - o ~o ~o ~o ~ - o ~o ~5 ~5 ~1 I c) c~- ct - c ~s ~ct - e~ ~ ~ ~ s ~ s - s ~ s ) - ~- v) - ~- ~- ~- c ~.. c~ e~ e~ e~ e~ c-) - c-~) - c.) - c) - ~ - c) · - ct · - ct · - ct · - ct · - ct · oD c) ~ c~ ~ c) oc O U:l O · V: O · U:} O · V: O C': O o ~ o ~ o ~ o ~ o ~ o · - -= · - ~ · - - c · - -= · - - ~ · - ~ ~ ~ ~ ~ m ~ ~ ~ o: G~ x X O O ~ X G ~0N ~G~ _ _ _ _ Ct V e . ~_ ,, ~, _ . u ~CC ~ ~ ~I ~
120 BEACH NOURISHMENT AND PROTECTION considered in this review'. Results from these studies indicate that recovery periods have been quite variable, ranging in duration from a few months to several years. The abundance and diversity of benthic fauna within the borrow sites often returned to levels comparable to prenourishment or reference condi- tions within a relatively short time (less than 1 year). However, several studies documented changes in the species composition of the benthos that lasted much longer, particularly in areas where bottom sediment composition was altered (Johnson and Nelson, 1985; Bowen and Marsh, 1988; Van Dolah et al., 1992, 1993; Wilber and Stern, 19921. The consequences of these long-term alterations are not well understood, especially with respect to how changes in species com- position affect the functional structure and trophic contribution of these commu- nities to marine predators that rely on the benthos as a primary food source. In some cases, long-term changes in the bottom habitat may alter the bottom com- munities or bottom habitats in a way that is perceived to be an improvement over the preexisting condition. For example, dredging down to hard substrata may result in increased biological diversity through the creation of reef habitat. Based on the limited number of studies that have been conducted in borrow areas to date, there appears to be considerable variability in the physical and ecological responses that have occurred after completion of a project. More moni- toring should be conducted to resolve whether these areas return to the physical and biological conditions that existed before dredging and, if so, how long it takes. This monitoring is particularly needed in regions where there has been little, if any, physical or biological monitoring of borrow areas used for beach nourishment projects. Until there is a better understanding of the ecological con- sequences of these projects, the most prudent action would be to design projects so that alterations in the physical conditions and biological resources of a borrow site are minimized or are short term relative to the planned frequency of renourishment. RESTORATION OF ABANDONED PROJECTS In Chapter 2, in the discussion of economic issues, it was clearly stated that beach renourishment may not continue to be a viable alternative indefinitely. That is, even for those programs that are presently viable, future conditions may change such that they are abandoned. Abandoning a beach nourishment project has certain predictable results. In the case of projects utilizing hard structures, as described in Chapter 4, those structures may be required to be removed upon abandonment of the project. However, there are other, perhaps more significant, consequences from other structures such as homes and streets. Although these are not strictly a part of the beach protection process, the environmental impacts of allowing these structures to remain in the face of an eroding shoreline are such that the problem needs to be firmly addressed in state and local coastal plans. In particular,~the restoration of dunes and dune plants in any area that was previ
ENVIRONMENTAL ISSUES ASSOCIATED WITH BEACH NOURISHMENT 121 ously developed and now has become part of the active beach because of aban- donment strategies now becomes a critical requirement. It appears that federal funding would not be available to assist in this operation under present regula- tions, so state and local agencies must plan for adequate resources to accomplish these objectives. Studies of the restoration of aquatic ecosystems (NRC, 1992) and on restoring marine habitat (NRC, 1994) provide guidance for these activi- ties. REFERENCES Ackerman, R. A. 1991. Physical factors affecting the water exchange of buried eggs. Pp. 193-211 in C. Deeming, and M. Gerguson, eds., Egg Incubation Its Effect on Embryonic Development in Birds and Reptiles. Cambridge, England: Cambridge University Press. Ackerman, R. A., T. Rimkus, and R. Horton. 1991. The Hydric Structure and Climate of Natural and Renourished Sea Turtle Nesting Beaches Along the Atlantic Coast of Florida. Unpublished report prepared by Iowa State University for Florida Department of Natural Resources, Talla- hassee. Ackerman, R. A., T. Rimkus, and R. Horton. 1992. Hydric and Thermal Characteristics of Natural and Renourished Sea Turtle Nesting Beaches Along the Atlantic Coast of Florida. Unpublished report prepared by Iowa State University for Florida Department of Natural Resources, Talla- hassee. Baca, B. J., and T. E. Lankford. 1988. Myrtle Beach nourishment project. Biological monitoring report Years 1, 2, 3 submitted to City of Myrtle Beach by Coastal Science and Engineering, Inc. CSE87-88 R- 1 1. 46 p. Bell, S. S. 1992. Upham Park beach nourishment project. The effect of sedimentation on macroinfauna, one year post-nourishment studies. Report submitted to Pinellas County Coastal Management Division, Clearwater, Fla. 27 pp. Bowen, P. R., and G. A. Marsh. 1988. Benthic Faunal Colonization of an Offshore Borrow Pit in Southeastern Florida. Miscellaneous Paper D-88-5. Vicksburg, Miss.: U.S. Army Engineer Waterways Experiment Station, U.S. Army Corps of Engineers. Broadwell, A. L. 1991. Effects of Beach Renourishment on the Survival of Loggerhead Sea Turtles. Unpublished master's thesis, Florida Atlantic University. Coastal Planning and Engineering, Inc. 1987. Environmental monitoring report for the 1984 Delray Beach Maintenance Nourishment Project. Boca Raton, Fla. 25 pp. Coastal Planning and Engineering, Inc. 1992. Boca Raton Beach Restoration Project: Three Year Post-Construction, Vol. I. Environmental monitoring report prepared for the city of Boca Raton, Fla. Continental Shelf Associates, Inc. 1992. Boca Raton beach restoration project. Three year post- construction. Vol. I. Environmental monitoring report prepared for the City of Boca Raton, Fla. Continental Shelf Associates, Inc. (Jupiter/Tequesta, Fla.) and Tropical Ecosystems, Inc. (West Palm Beach, Fla.). 1984. Biological analysis of macroepibiotal and macroinfaunal assemblages fol- lowing beach nourishment in North Broward County, Florida. Study prepared for the Broward County Environmental Quality Control Board. 30 pp. Courtenay, W. R., Jr., D. J. Herrema, M. J. Thompson, W. P. Azzinaro, and J. Van Montfrons. 1972. Ecological monitoring of two beach nourishment projects in Broward County, Florida. Shore and Beach 40:9-13.
122 BEACHNOURISHMENT AND PROTECTION Courtenay, W. R., Jr., D. J. Herrema, M. J. Thompson, W. D. Azzinaro, and J. van Montfrans. 1974. Ecological Monitoring of Beach Erosion Control Project, Broward County, Florida and Adja- cent Areas. Technical Memorandum No. 41. Washington, D.C.: Coastal Engineering Research Center, U.S. Army Corps of Engineers. Courtenay, W. R., Jr., B. C. Hartig, and G. R. Loisel. 1980. Ecological Evaluation of a Beach Nourishment Project at Hallandale (Broward County), Florida: Evaluation of Fish Populations Adjacent to Borrow Areas of Beach Nourishment Project, Hallandale (Broward County), Florida, Vol. I. Miscellaneous Report 80-1(I). Fort Belvoir, Va.: Coastal Engineering Research Center, U.S. Army Corps of Engineers. Croker, R. A., R. P. Hager, and K. J. Scott. 1975. Macroinfauna of northern New England marine sand, Vol. II. Amphipod-dominated communities. Canadian Journal of Zoology 53:42-51. Cutter, J. K., and S. Mahadevan. 1982. Long-term effects of beach nourishment on the benthic fauna of Panama City Beach, Florida. U.S. Army Corps of Engineers, Coastal Engineering Research Center, Misc. Rept. No. 82-2. Dahl, E. 1952. Some aspects of the ecology and donation of the fauna on sandy beaches. Oikos 4:1 27. Deis, D. R., K. W. Spring, and A. D. Hart. 1992. Captiva Beach restoration project biological monitoring program. Pp. 227-241 in New Directions in Beach Management: Proceedings of the 5th Annual National Conference on Beach Preservation Technology. Tallahassee, Fla.: Florida Shore and Beach Preservation Association. Dexter, D. M. 1972. Comparison of the community structure in a Pacific and Atlantic Panamanian sandy beach. Bulletin Marine Science 22:449-462. Dodd, C. K., Jr. 1988. Synopsis of the Biological Data on the Loggerhead Sea Turtle, Caretta caretta (Linnaeus, 1758). Biological Report 88(14). FAO Synopsis NMFS-149. Washington, D.C.: U.S. Fish and Wildlife Service. Federal Register. 1993. Endangered and threatened wildlife and plants; Amaranthus pumilus (Seabeach Amaranth) determined to be threatened. 50 CFR Part 17, Vol. 58. No. 65. Fisher, L. E., R. E. Dodge, C. G. Messing, W. M. Goldberg, and S. Hess. 1992. The first renourishment at Hollywood and Hallandale (Florida) beaches: Monitoring of sediment fallout, coral communities and macroinfauna: preliminary results. Pp. 209-227 in S. Tait, ea., New Directions in Beach Management. Proceedings of the 5th Annual National Conference on Beach Preservation Technology. Florida Shore and Beach Preservation Association. Flynn, B. 1992. Beach nourishment, sea turtle nesting, and nest relocation in Dade County, Florida. Proceedings of the 1992 National Conference on Beach Preservation Technology. St. Peters- burg, Fla. Flynn, B. S., S. M. Blair, and S. M. Markley. 1991. Environmental monitoring of the Key Biscayne beach restoration project. Pp. 234-247 in S. Tait, ea., Preserving and Enhancing Our Beach Environment. Proceedings of the 1991 National Conference on Beach Preservation Technol- ogy. Florida Shore and Beach Preservation Association. Goldberg, W. M. 1985. Long term effects of beach restoration in Broward County, Florida. A three year overview. Unpublished report to Broward County Environmental Quality Control Board and Erosion Prevention District. 51 pp. Goldberg, W. M. 1989. Biological effects of beach nourishment in south Florida: the good, the bad and the ugly. In: Proceedings of Beach Preservation Technology 1988. Tallahassee: Florida Shore and Beach Preservation Association. Gorzelany, F. J., and W. G. Nelson. 1987. The effects of beach replenishment on the benthos of a subtropical Florida beach. Marine Environmental Research 21:75-94. Grober, L. E. 1992. The Ecological Effects of Beach Replenishment. Unpublished master's thesis, Duke University School of the Environment.
ENVIRONMENTaL ISSUES ASSOCIATED WITH BEACH NOURISHMENT 123 Hayden, B., and R. Dolan. 1974. Impact of beach nourishment on distribution of Emerita talpoida, the common mole crab. J. Waterways, Harbors and Coastal Engineering Division. American Society of Civil Engineers 100:123-132. Higgins, S. 1993. Long-term benefits of turtle nest relocation and protection programs at Broward County and Jupiter Island, Florida. In: Sixth Annual National Conference on Beach Preserva- tion Technology. Tallahassee: Florida Shore and Beach Preservation Association. Hobbs, C. H., III. 1993. Sand mining in lower Chesapeake Bay: A progress report. Marine Georesources and Geotechnology 11: 347-352. Holland, H. T., J. R. Chambers, and R. R. Backman. 1980. Effects of Dredging and Filling for Beach Erosion Control on Fishes in the Vicinity of Lido Key, Florida. Unpublished report. Jackson- ville, Fla.: Jacksonville District, U.S. Army Corps of Engineers. Jaap, W. C. 1984. The Ecology of the South Florida Coral Reefs: A Community Profile. Report No. EWS/OBS-82/08. Washington, D.C.: U.S. Fish and Wildlife Service. Johnson, R. O., and W. G. Nelson. 1985. Biological effects of dredging in an offshore borrow area. Florida Scientist 48:166-188. Kana, T. W. 1990. Conserving South Carolina Beaches Through the 1990s: A Case for Beach Nourishment. Report prepared for South Carolina Coastal Council, Charleston, S. C. Knott, D. M., D. R. Calder, and R. F. Van Dolah. 1983. Macrobenthos of sandy beach and nearshore environments at Murrell's Inlet, South Carolina, USA, estuarine coast. Shelf Scientist 16:573- 590. LeBuff, C. R., Jr., and E. M. Haveffield. 1990. Nesting success of the loggerhead turtle (Caretta caretta) on Captiva Island, Florida, a nourished beach. Unpublished data. Sanibel Island, Fla.: Caretta Research. Lynch, A. E. 1994. Macrofaunal recolonization of Folly Beach, South Carolina, After Beach Nour- ishment. Unpublished master's thesis, University of Charleston, Charleston, S. C. Marsh, G. A., P. R. Bowen, D. R. Deis, D. B. Turbeville, and W. R. Courtenay, Jr. 1980. Ecological Evaluation of a Beach Nourishment Project at Hallandale (Broward County), Florida. Vol. II. Evaluation of Benthic Communities Adjacent to a Restored Beach, Hallandale (Broward County), Florida. Miscellaneous Report 80-1(II). Fort Belvoir, Va.: Coastal Engineering Re- search Center, U.S. Army Corps of Engineers. Maurer, D., R. Keck, J. C. Tinsman, W. A. Leathem, C. A. Wethe, M. Huntzinger, C. Lord, and T. M. Church. 1978. Vertical Migration of Benthos in Simulated Dredged Material Overburdens. Vol. I: Marine Benthos. DMRP Technical Report D-78-35. Report prepared by University of Delaware, College of Marine Studies. Vicksburg, Miss.: U.S. Army Engineer Waterways Ex- periment Station, U.S. Army Corps of Engineers. Maurer, D., R. Keck, J. C. Tinsman, and W. A. Leathem. 1981a. Vertical migration and mortality of benthos in dredged material. I. Mollusca-Mar. Environmental Research 4:299-319. Maurer, D., R. Keck, J. C. Tinsman, and W. A. Leathem. 1981b. Vertical migration and mortality of benthos in dredged material. II. Crustacea-Mar. Environmental Research 5:301-317. Maurer, D., R. Keck, J. C. Tinsman, and W. A. Leathem. 1982. Vertical migration and mortality of benthos in dredged material. III. Crustacea-Mar. Environmental Research 6:49-68. Maurer, D., R. T. Keck, H. C. Tinsman, W. A. Leathem, C. Wethe, C. Lord, and T. M. Church. 1986. Vertical migration and mortality of marine benthos in dredged material; a synthesis. Interna- tional Revue Hydrobiology 71:49-63. Melvin, S. M., C. R. Griffin, and L. H. MacIvor. 1991. Recovery strategies for piping plovers in managed coastal landscapes. Coastal Management 19:21-34. Murawski, W. S. 1969. A Study of Submerged Dredge Holes in New Jersey Estuaries with Respect to Their Fitness as Finfish Habitat. Miscellaneous Report No. 2M. Division of Fish and Game, New Jersey Department of Conservation and Economic Development.
24 BEACH NO URISHMENT AND PROTECTION Naqvi, S., and E. Pullen. 1982. Effects of Beach Nourishment and Borrowing on Marine Organisms. Miscellaneous Report No. 82-14. Fort Belvoir, Va.: Coastal Engineerin;, Research Center, U.S. Army Corps of Engineers. Nelson, D. A. 1991. Issues associated with beach nourishment and sea turtle nesting. Pp. 277-294 in Preserving and Enhancing Our Beach Environment: Proceedings of the 4th Annual National Beach Preservation Technology Conference. Tallahassee: Florida Shore and Beach Preserva- tion Association. Nelson, D. A., and D. Dickerson. 1988. Hardness calf Nourished and Natural Sea Turtle Nesting Beaches on the East Coast of Florida. Unpublished report. Vicksburg, Miss.: U.S. Army Engi- neer Waterways Experiment Station, U.S. Army Corps of Engineers. Nelson, D. A., K. A. Mauck, and J. Fletemeyer. 1987. Physical Effects of Beach Nourishment on Sea Turtle Nesting, Delray Beach, Florida. Technical Report No. TR-87-15. Vicksburg, Miss.: U.S. Army Engineer Waterways Experiment Station, U.S. Army Corps of Engineers. Nelson, W. G. 1985. Physical and Biological Guidelines for Beach Restoration Projects. Part I. Biological Guidelines. Report No. 76. Florida Sea Grant College, Gainesville. Nelson, W. G. 1989. An overview of the effects of beach nourishment on the sand beach fauna. Pp. 295-309 in Proceedings of the 1988 National Conference on Beach Preservation Technology. Tallahassee: Florida Shore and Beach Preservation Association. Nelson, W. G. 1990. Beach nourishment and hard-bottom habitats: the case for caution. Pp. 109-116 in Proceedings of the 1989 National Conference on Beach Preservation Technology. Tallahas- see: Florida Shore and Beach Preservation Association. Nelson, W. G. 1991. Methods of biological monitoring of beach restoration projects: problems and solutions in the real world. Pp. 263-276 in Preserving and Enhancing Our Beach Environment: Proceedings of the 1991 National Conference on Beach Preservation Technology. Tallahassee: Florida Shore and Beach Preservation Association. Nelson, W. G. 1993. Beach restoration in the southeastern US: environmental effects and biological monitoring. Ocean and Coastal Management 19:157-182. Nelson, W. G., and G. W. Collins. 1987. Effects of Beach Nourishment on the Benthic Macrofauna and Fishes of the Nearshore Zone of Sebastian Inlet State Recreation Area. Unpublished report to Jacksonville District, U.S. Army Corps of Engineers from the Department of Oceanology and Ocean Engineering, Florida Institute of Technology. NRC. 1992. Restoration of Aquatic Ecosystems: Science, Technology, and Public Policy. Water Science Board, Commission on Geosciences, Environment, and Resources. Washington, D.C.: National Academy Press. NRC. 1994. Restoring and Protecting Marine Habitat. Marine Board, Commission on Engineering and Technical Systems. Washington, D.C.: National Academy Press. Paar, T., D. Diener, and S. Lacy. 1978. Effects of Beach Replenishment on the Nearshore Sand Fauna at Imperial Beach, California. Miscellaneous Report 78-4. Fort Belvoir, Va.: Coastal Engineering Research Center, U.S. Army Corps of Engineers. Rackocinski, C., S. E. LeCroy, J. A. McLelland, and R. W. Heard. 1991. Responses by Macroinvertebrate Communities to Beach Nourishment at Perdido Key, Florida: Initial Faunal Impact. Semiannual Report No. GCRL 03:06-30-91 prepared by Gulf Coast Research Labora- tory. Ocean Springs, Miss.: National Park Service. Rackocinski, C., S. E. LeCroy, J. A. McLelland, and R. Heard. 1992. Responses by Macroinvertebrate Communities to Beach Renourishment at Perdido Key, Florida: monitoring phase. Semiannual Report No. GCRL 05:06-30-92 prepared by Gulf Coast Research Laboratory. Ocean Springs, Miss.: National Park Service. Raymond, P. W. 1984. The Effects of Beach Restoration `.,n Marine Turtles Nesting in South Broward County, Florida. Unpublished master's thesis, University of Central Florida, Orlando. Reilly, F., Jr. 1979. A Study of the Ecological Impact of Beach Nourishment with Dredged Materials on the Intertidal Zone. Unpublished master's thesis, East Carolina University.
ENVIRONMENTAL ISSUES ASSOCIATED WITH BEACH NOURISHMENT 125 Reilly, F., Jr., and V. Bellis. 1978. A Study of the Ecological Impact of Beach Nourishment with Dredged Material on the Intertidal Zone. Technical Report No. 4. Institute for Coastal and Marine Resources, East Carolina University. Ryder, C. E. 1992. The effect of beach renourishment at Sebastian Inlet State Recreation Area. Unpublished master's thesis, Virginia Polytechnic Institute, Blacksburg. Saloman, C., S. Naughton, and J. Taylor. 1982. Benthic Community Response to Dredging Borrow Pits, Panama City Beach, Florida. Miscellaneous Report No. 82-3. Fort Belvoir, Va.: Coastal Engineering Research Center, U.S. Army Corps of Engineers. Schaffner, L. C., and C. H. Hobbs, III. 1992. Effects of sand-mining on benthic communities and resource value: Thimble Shoal, lower Chesapeake Bay. Technical report from the Virginia Institute of Marine Science, Gloucester Point, Va. under contract with the Virginia Department of Conservation and Recreation via the Joint Commonwealth Programs Addressing Shore Ero · · ~ r. · ~ slon In v 1rglma. Shelton, C. R., and P. B. Robertson. 1981. Community structure of intertidal macrofauna on two surf-exposed Texas sandy beaches. Bulletin of Marine Sciences 31:833-842. Spadoni, R. H. 1993. Environmental impacts of beach erosion. Presentation made at the Florida Shore and Beach Preservation Association Technical Conference on the "State of the Art in Beach Nourishment," St. Petersburg, Fla., February 10, 1993. Spadoni, R. H., and S. L. Cummings. 1992. A common sense approach to the protection of marine turtles. New Directions in Beach Management: Proceedings of the 5th Annual National Confer- ence on Beach Preservation Technology. Tallahassee: Florida Shore and Beach Preservation Association. Steinitz, J. 1990. Reproductive Success of Sea Turtles on Jupiter Island, Florida, 1990. Unpublished report prepared for town of Jupiter Island. Strock, A. V., and Associates, Inc. 1983. Five year environmental follow-up reef survey for the 1978 Delray Beach maintenance nourishment project. Report submitted to the City of Delray Beach, Florida. 23 p. Trevallion, A., A. D. Ansell, P. Sivadas, and B. Narayanan. 1970. A preliminary account of two sand beaches in southwest India. Marine Biology 6:268-279. Turbeville, D. B., and G. A. Marsh. 1982. Benthic fauna of an offshore borrow area in Broward County, Florida. U.S. Army Corps of Engineers Coastal Engineering Research Center. Misc. report 82-1. pp. 1-43. USFWS. 1993. Endangered and Threatened Wildlife and Plants. Notice 50 CFR 17.11 and 17.12, August 23. Washington, D.C.: U.S. Fish and Wildlife Service. Van Dolah, R. F., and D. M. Knott. 1984. A Biological Assessment of Beach and Nearshore Areas Along the South Carolina Grand Strand. Final report. Agreement No. 14-16-004-84-924. Pre- pared for the U.S. Department of the Interior. Charleston, S. C.: U.S. Fish and Wildlife Service. Van Dolah, R. F., P. H. Wendt, R. M. Martore, M. V. Levisen, and W. A. Roumillat. 1992. A Physical and Biological Monitoring Study of the Hilton Head Beach Nourishment Project. Unpublished report prepared by South Carolina Wildlife and Marine Resources Department for Town of Hilton Head Island, S. C. Van Dolah, R. F., R. M. Martore, and M. V. Levisen. 1993. Physical and Biological Monitoring Study of the Hilton Head Beach Nourishment Project. Supplemental report prepared by the South Carolina Marine Resources Research Institute for the town of Hilton Head Island, S. C. Van Dolah, R. F., R. M. Martore, A. E. Lynch, M. V. Levisen, P. H. Wendt, D. J. Whitaker, and W. D. Anderson. 1994. Environmental Evaluation of the Folly Beach Nourishment Project. Final report, Charleston District, U.S. Army Corps of Engineers, and the Marine Resources Division, South Carolina Department of Natural Resources. Watts, G. M. 1963. Behavior of offshore borrow zones in beach fill operations. Pp. 17-24 in Interna- tional Association for Hydraulic Research (IAHR) Tenth Congress, Vol. 1. London: IAHR.
26 BEACHNOURISHMENT AND PROTECTION Wilber, P., and M. Stern. 1992. A re-examination of infaunal studies that accompany beach nourish- ment projects. Pp. 242-257 in New Directions in Beach Management: Proceedings of the 5th Annual National Conference on Beach Preservation Technology. Tallahassee: Florida Shore and Beach Preservation Association. Williams, S.J., S. Penland, and A.H. Sallenger Jr., eds. 1992. Louisiana barrier island erosion study. Atlas of Shoreline Changes in Louisiana from 1853 to 1989. USGS Misc. Inv. Series. No. I- 2150-A. 107 pp. Williams, A. B. 1984. Shrimps, lobsters, and crabs of the Atlantic coast of the eastern United States, Maine to Florida. Washington, D.C.: Smithsonian Institution Press. Witham, R. 1990. A case report on beach erosion, beach nourishment, and sea turtle nesting. Pp. 157-160 in Proceedings of the 10th Annual Workshop on Sea Turtle Biology and Conservation. NOAA Technical Memorandum NMFS-SEFC-278. Washington, D.C.: National Oceanic and Atmospheric Administration.