points out, hov.'Gvor, the conceivabil ity of 

 how a manmade nodification at some dis- 

 tance nay have pronounced effects on the 

 life history and abundance of organisms. 



It is interesting to note that the 

 fishing guides regarded the lush, produc- 

 tive turtle grass beds as a pest and much 

 desired the muddy, sparse shoal grass. 

 What this really illustrates is that quite 

 different habitats may be of vital impor- 

 tance to certain species at specific 

 points in their life cycle. Those fea- 

 tures that make the turtle grass beds good 

 nurseries and important to these same car- 

 nivores when they are juveniles restrict 

 their foraging ability as adults. It 

 should be noted in passing that while 

 lamenting the encroachment of turtle grass 

 into this area, the guides still hailed 

 the shallow turtle grass beds to be super- 

 ior bonefish habitat. 



8. 



The rate at which a disturbed tropi- 

 cal grass bed may recolonize is still 

 largely unknown. Fuss and Kelly (1969) 

 found that at least 10 months were re- 

 quired for a turtle grass rhizome to 

 develop a new apex. 



The most common form of disturbance 

 to seagrass beds in south Florida involves 

 cuts from boat propellers. Although it 

 would seem that these relatively small- 

 scale disturbances would heal rapidly, 

 typically it takes 2 to 5 years to recolo- 

 nize a turtle grass bed (Zieman (197G). 

 Although the scarred areas rapidly fill in 

 with sediment from the surrounding beds, 

 the sediment is slightly coarser and has a 

 lower pH and Eh. 



In some regions, disturbances become 

 nearly permanent features. Off the coast 

 of Belize aerial photographs show features 

 in the water that appear as strings of 

 beads. These are holes resulting from 

 seismic detonation; some have persisted 

 for over 17 years (J.C. Ogden, personal 

 communication) with no recolonization. 

 This is not just due to problems associ- 

 ated with explosions, as Zieman has obser- 

 ved blast holes from bombs on a naval 

 bombing range in Puerto Rico where some 

 recolonization occurred within 5 years. 



Most cases nf restoration in south 

 Florida involve turtle grass because of 

 its value to the ecosystem and its spatial 

 dominance as well as its truculence at 

 recolonizing a disturbed area. Recoloni- 

 zation by shoal grass is not frequently a 

 problem. The plant has a surficial root 

 and rhizome system that spreads rapidly. 

 It grows from remaining fragments or from 

 seed and can recolonize an area in a short 

 time. 



Ry comparison, turtle grass is much 

 slower". Fuss and Kelly (1969) found 10 

 months were required for turtle grass to 

 show new short shoot development. The 

 short shoots seem to be sensitive to envi- 

 ronmental conditions also. Kelly et al . 

 (1971) found that after 13 months 40°^ of 

 the transplants back into a central area 

 had initiated new rhizome growth, while 

 only 15°^ to 18% of the plants showed new 

 growth initiation v/hen transplanted to 

 disturbed sediments. Thorhaug (1974) 

 reported success with regeneration from 

 turtle grass seedlings, but unfortunately 

 seeding of turtle grass in quantity is a 

 sporadic event in south Florida. 



If one accepts the concept of ecolog- 

 ical succession, there are two basic ways 

 to restore a mature community: (1) estab- 

 lish the pioneer species and allow succes- 

 sion to take its course, and (2) create 

 the environmental conditions necessary for 

 the survival and growth of the climax spe- 

 cies. Van Breedveld (1975) noted that 

 survival of seagrass transplants was 

 greatly enhanced by using a "ball" of sed- 

 iment, similar to techniques in the ter- 

 restrial transplantation of garden plants. 

 He also noted that transplantation should 

 be done when the plants are in a semidor- 

 mant state (as in winter) to give the 

 plants time to stabilize, again a logical 

 outgrowth of terrestrial technique. 



Although numerous seagrass trans- 

 plantings have been performed in south 

 Florida, the recent study by Lewis et al . 

 (1981) is the first to use all major sea- 

 grass species in a comprehensive experi- 

 mental design that tests each of the tech- 

 niques previously described in the litera- 

 ture. The study site was a 10-ha (25-acre) 

 borrow pit on the southeast side of Craig 

 Key in the central Florida Keys, which was 

 studied from February 1979 to February 



91 



