Lively Raimondi reading wk3

Lively Raimondi reading wk3 - Oecologin (BCELLBALU 987)...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 4
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 6
Background image of page 7
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Oecologin (BCELLBALU 987) 7413047309 l ill ll flembgia E Springer-Verlag 1987 -| Will Desiccation, predation, and mussel-barnacle interactions in the northern Gulf of California CM. Lively“*, and P.T. Rairnondil 1 Department of Ecology and Evolutionary Biology. University ofArizona. Tucson. AZ. 85721, USA 3 Department of Biological Sciences. University of California, Santa Barbara. CA 93106, USA Summary. Field experiments were conducted in order to determine the potential for desiccation and predation to mediate the effect of mussels (Brrrr'l'n'dontes syndicates) on barnacles (Clu/mmn/us unisopoma) in the highly seasonal northern Gulf of California. We did this by removing both mussels and a common mussel predator (Mar'at'aferrugz‘n- om: Gastropoda) and by spraying selected sites with sea water during summertime spring low tides. We also deter‘ mined the effect of crowding on resistance to desiccation in barnacles, and the effect of barnacles on colonization by mussels. The mussel—barnacle community was not af- fected by keeping experimental quadrats damp during day- time low tides throughout the summer. Exposure to sum- mertime low tides, however, did affect the survivorship of isolated, but not crowded, barnacles; and barnacle clumps enhanced the recruitment of mussels. Hence crowding in barnacles had a positive effect on both barnacle survivor- ship and mussel recruitment. Momch had a negative effect on mussel density, and mussels had a negative effect on barnacle density. The effect of Morula on barnacle density was positive, presumably due to its selective removal of mussels. These results suggest an indirect mutualism be- tween barnacles and the gastropod predator, because bar- - nacles attract settlement or enhance the survival of mussels, and the predator reduces the competitive effect of mussels on barnacles. Key words: Barnacles — Competition — Desiccation i Mus- sels — Predation Studies of structure in marine, freshwater, and terrestrial communities have demonstrated that competition (reviews in Connell 1983; Schoener 1983), predation (e.g. Connell 1961; Paine 1966a, 1971, 1974; review in Sih et a1. 1985), physical stress (eg. Bertness 1981; Garrity and Levings 1981; review in Connell 1972), disturbance (e.g. Dayton 1971; Connell 1978; Sousa 1979; review in Sousa 1984) and recruitment patterns (e.g. Sale 1977; Connell 1985; Rai- mondi unpublished work) are all factors which contribute to the coexistence of multiple interacting species. A number * Present address and address for ofl’prim‘ requests: Department of Zoology, University of Canterbury, Christchurch 1, New Zea— land of these studies have successfully combined the concomitant effects of several of these factors (e.g. Dayton 1971 ; Menge 1976, 1978a, b; Lubchenco 1978; Morin 1983: review in Sih et al. 1985), and some recent experiments have eluci- dated significant indirect effects among species, which result from interactions between competition and predation (eg. Lubchenco I978; Dethier and Duggins 1984; Davidson et al. 1984; Dungan 1986, 1987). In the present study, we evaluated the effects of competition, predation, and tem- porally variable physical stress on an intertidal mussel-bar— nacle community in the highly seasonal northern gulf of California. The rocky intertidal region in the northern Gulf of Cali— fornia is unique in several interesting ways, which makes it an excellent place to test current generalizations regarding the mechanisms underlying the structure of such communi- ties (see Underwood and Denley 1984). For example, the two major barnacle species are zoned “upside down"; that is the larger species (Tetraclita) is zoned above the smaller species (Chthamalus), rather than below as is usually the case (Dungan 1985). Similarly, the mid-intertidal mussel population (Brachidomes semilaeuis) differs from the well- studied Mytilus populations of more temperate shores in several ways: (1) Brachidontes are small (<10 mm); (2) they are distributed throughout the barnacle zone; and (3) they are generally somewhat rare (see also Menge and Lub- chenco 1981). Observations of permanent quadrats between 1980 and 1986 indicated a trend for Brochidonres to un- dergo a recruitment pulse during the early summer, then die back during the late summer; a decrease in barnacle (Chthamalus anisopoma) densities corresponds with this early—summer increase by mussels (Lively, Raimondi and Delph, unpublished work). During a particularly large set- tlement in 1981, Brachidomes was observed at one site to go from being rare (<5% cover) in the early summer to being abundant (> 70% cover) by mid summer, overgrow— ing the barnacle population in the process. By late summer the mussels had disappeared, leaving bare rock. In the present study, we tested three hypotheses (in their null forms) regarding these observations: (1) mussels are killed in the late summer by desiccation; (2) the pulse in mussel settlement temporarily swamps the ability of a gas- tropod predator to harvest them; and (3) mussels outcom- pete barnacles in the absence of (a) predation andjor (b) desiccation. We also determined the effect of crowding in barnacles on their resistance to desiccation, and the pres- ence of barnacles on settlement by mussels. wild-l. Sim (Md SPEC-fats description? The northern Gulf ofCalifornia is a highly seasonal marine unvironment. a result of its shallowness and the influence of the surrounding Sonoran Desert (Hendrickson 1973; Brusca 1980). In addition, waves are generally small and 1m. days clear, so there is little protection from stress im— posed by the atmosphere during daytime low tides. Thoma am and Lchncr (1976) recorded air temperatures below it“ t‘ in the winter and above 40°C in the summer {see film) llcndrickson 1973). and we have recorded rock surface temperatures as high as 52° C during the summer. (Virlnmiafns rmisopnmrr is a small acorn barnacle (maxi— mum diameter 7 mm) that dominates space in the mid-inter tidal throughout the Gulf of California, and commonly 0C- L-urs in densely packed aggregations (Dungan 1985, 1986; Lively 1986a). Such aggregations rcduce growth rates and enhance the probability of removal by wave action, but there is no significant adult mortality that results directly {mm crowding (Lively 1986b: see also Luckens 1975). The harnacle ranges from about 0 1.8 in above mean low water (MLW) in the northern Gulf of California (Dungan 1985). Brrrrhidomes sentiments is a small intertidal mussel (maxi imtnn length approximately 10 mm) that overlaps with ('r'rrl’mmalus: and like the barnacle (see Malusa 1986; Dunn gun 1986), it shows a peak in recruitment during the sum- mer months. It is the preferred prey of the small (approxi~ Inately 12 mm) gastropod Morninfermginosa (Raimondi, unpublished work). Morale forages when inundated and is less restricted to cracks and crevices than is Acamhina (Lively 1986a), which forages during periods of tidal expo- sure and specializes on barnacles (Paine 1966b; Dungan I987). The experiments that follow were conducted on rocky intertidal shores in the northern Gulf of California near the town of Puerto Pefiasco (31°20’N, 113°40’W), Sonora, Mexico (see Malusa 1986 for a location map). The barnacle desiccation experiment was conducted at Playa Las Con- chas (Shell Beach), a limestone reef with basalt boulders 5 km east of Puerto Peiiasco. The remaining experiments were conducted at Punta Pelicano (Pelican Point), a granitic headland 10 km northwest of Puerto Pefiasco. Both study sites were on horizontal shelves having direct exposure to wave action. Methods and materials Competition and desiccation. In order to determine whether mussels are killed in the late summer by desiccation, and whether mussels outcompete barnacles in the absence of such stress, we established sixteen 10 x 10 cm quadrats (on 25 May 1982) at Pelican Point at each of two areas at site “A” (+1 m above MLW). The corners of the quadrats were marked using a marine epoxy, and the quadrats were randomly assigned to be one (of four) replicates of the fol- lowing four treatments: (1) mussels removed (using tweezers), and the quadrat kept moist during spring low tides by periodically spraying with fresh seawater; (2) mus— sels removed, but the quadrat not sprayed during low tides; l3) quadrat sprayed, but mussels not removed; and (4) quadrats not sprayed, and mussels not removed (see Ta- ble 1). The quadrats were sampled after six and twelve wks by using a clear plexiglass plate with 100 randomly placed dOLs in a 10 cm x 10 cm area, and by counting the number 305 ill ll Table l. The design of the competition, predation, and desiccation experiment, giving the number of quadrats in sites A and B for each of the four treatments in the predator removal and predator control areas Predator control area Predator rell'lOVEll area Treatment Site A [. Mussel removal, spray 4 4 2, Mussel removal, no spray 4 4 3. Mussel control, spray 4 4 4. Mussel control, no spray 4 4 Site B 4. Mussel control, no Spray 4 4 of dots directly over barnacles and mussels in each quadrat, to give an estimate of the percentage of rock surface covered by each (after Connell 1970). We assessed the potential effect of natural wave splash on our quadrats by recording the time of inundation at site A and comparing this to the time of inundation at a protected site at the same tidal height. The difference between the two times served as an indication of the effect of natural wave action on reducing exposure time. Predation. To determine the effect of predation by Morula on the mussel—barnacle community, we manually removed it from one (randomly selected) of the two areas at site A once each day during spring low tides. To replicate the Month: removal in space, we established another four quad- rats on 7 July 1982 at each of two additional areas at a second site, site “B” (also +1 m above‘MLW), and we removed Morula from the vicinity of one of the areas (ran- domly selected); the quadrats at site B were sampled six wks later using the random—dot method described above. A third site (“C”) was also established, but it was later abandoned because we were unable to decrease the densities of foraging Mamie in the removal area. Note that, unlike the mussel removal and spray treat- ments, the quadrats could not be randomly assigned with respect to the Marula removal treatment [We used manual removals instead of cages, because Morale are small enough to pass through standard mesh sizes large enough to prevent cage effects (personal observations)]. The layout of quad— rats is summarized in Table 1. We assessed the effectiveness of the Morula removals at site A three times during the course of the experiment by using snorkeling equipment. When the site was inun- dated by approximately 2 m of water, we dropped a stain- less steel n‘ng (diameter: 30.5 cm) from the surface onto the removal and control areas at site A, and we counted all Manda within the ring. A sample consisted of four repli- cates of this procedure within each area. A datum was con- sidered to be the average of these four replicates. The mean density of Morula for the three samples in the control area was 105 m’2 (SE:20.52). This was significantly greater than the mean density (it: 1.13; SE=1.13) in the removal area (paired I: 5.13; d.f.=2; P< 0.025). Hence, the manual removals of Morula were effective in reducing its densities during Spring low tides. This predator, however, reinvaded the removal areas during neap tidal series; so we reduced, but did not eliminate the effects of predation. 306 _ o Barn—ocles o Mussels — Morale control — - Moro/a removal Mussel removal Site A Mussel control Site A PERCENT COVER IT Aug 25Moy TlME 7 July Table 2. ANOVA Summary for the percentages of quadrats covered by mussels and barnacles at the end of the mussel removal/spray experiment. Data from site A Source d.f. Predator Predator (M 0min) (ll/forum) removal area control area MS P MS P Mussels Main effects Spray 1 5.06 0.748 36.06 0.495 Mussel removals 1 1743.06 < 0.001 588.06 0.012 Interaction 1 3.06 0.802 0.06 0.976 Error 12 46.65 66.81 Barnacles Main effects Spray 1 5.06 0.825 4.00 0.819 Mussel removals 1 390.06 0.071 72.25 0.340 Interaction 1 105.06 0.324 90.25 0.288 Error 12 99.19 73.13 Crowding and desiccation in bamacles. Keeping selected quadrats moist during low tides in the previous experiments had no effect on the mussel-barnacle community. This sug- gests the hypothesis that the closely-packed aggregations of barnacles (which characterized our study sites) might modify the environment in a way which is beneficial to both barnacles and mussels. To test the idea that crowded barnacles have a greater resistance to desiccation than iso- lated barnacles, we placed six basalt boulders having iso- lated Chrhamalus together in the intertidal zone at Shell Beach. On each boulder, 15—20 individuals of comparable size were selected and marked by placing a dab of nail polish nearby on the boulder. All individuals selected were at least 1 cm from their nearest conspecific. A second set of six boulders was collected, which had clumps of individ- uals in direct contact. Two such clumps, with a minimum of 20 adults in each, were marked as above on all six boulders. One boulder from each of the two “treatments” was then randomly assigned one of the following times for inundation: 10:30, 11:00, 11:30,12:00, 12:30, and 13:00 hours. Time at emersion was at about 06:00, so exposure time ranged from 4.5 to 7 h, which approximated the maxi- mum summertime exposure period for 1983 (see Thomson ITAug ll: I‘ll ll ll Mussel control Sile E! Fig. 1. Mean percentages of rook substrate covered by mussels and barnacles in the mussel and Morn/r: removal treatments. Both sprayed and unsprayed quadrats at site A were included in the calculation of the means at site A, because the effects of spray were not significant (P>0.49, Table 2). Vertical bars are i SE TJuly I7Aug 1983). Following inundation, which was simulated by dunk- ing the boulders in a tidepool, the number of surviving barnacles was counted by recording the number of feeding individuals. Individuals that did not feed within 5 mins of inundation were counted as dead (a further check on one set of boulders after 24h in natural conditions gave the same results as did the 5 min census). The experiment was conducted on 27 July and repeated On 12 August, 1983. Barnacles and mussel recruitment. The association between barnacles and mussels might be due, in part, to higher re- cruitment of mussels into areas containing barnacles (see Dayton 1971; Paine 1974; Menge 1976). To test this hy- pothesis, we established eight replicates of each of the fol- lowing four treatments at Pelican Point during the summer of 1984: (1) mussels removed, barnacles unmanipulated, (2) mussels removed, bamacles killed and their shells re- moved, (3) mussels removed, barnacles killed but their shells not removed, and (4) both mussels and barnacle un- manipulated. The treatments were performed on 5 x 5 cm quadrats, which were sampled every two wks using 25 ran- dom dots in the manner discussed above. Results Competition and desiccation. The spray treatment had no significant effect on mussels or barnacles in either the preda- tor removal area or the predator control area at site A (Table 2). There was also no significant spray >< mussel- removal interaction effect in either area. Hence, desiccation would not appear to explain the late summer decline in mussels. In addition, there was no recruitment of algae to the quadrats which we kept moist during tidal exposure, suggesting the absence of algal spores during the summer or the requirement of shade for summertime colonization by algae. The lack of response to the spray treatment would not appear to result from natural wetting due to wave action. The quadrats at site A were wetted by the incoming tide a mean of only 6.05 (SE=4.73, N: 39) min before the pro— tected site at the same tidal height. A mean air temperature of 3251" C (SE:O.43) was recorded just prior to inunda- tion of site A, following morning spring low tides. The removal of mussels, by contrast, had a marginally significant and positive effect on barnacles in the predator removal area at site A; but no such effect was observed in the predator control area (Fig. 1, Table 2). lilll Table 3. ANOVA summary and multiple range test for the desicca- tion experiment. Means are from untransformed data. Statistical mmlygis performed on transformed data (urcsine squarcroot, sec [or Source d.l‘. MS P Mnin clTects little 5 301.07 0010 Isolation l 1033.50 (0.001 iiitcl‘ut‘lton 5 255.20 0.013 [ii-rot 11 59.92 time of inundation Means Crowded Isolated m : 30 99a 96.5ab “:00 100a 96.5ab l l :30 1003 96.5 ‘h 13:00 100a 97.5uh 13: 30 99ah 54.06 13:00 100a 660be Means with the saute superscript are not significantly different tic. £50.05) by a least significant difference test Table 4. ANOVA summary multiple range test for the percentages or quadrats covered by mussels in the mussel settlement experi- ment. Statistical tests performed on transformed data (arcsine squareroot); means are from untransformed data Sourc: d.f. MS P _____H_4_____me.__ Treatment 3 1346.89 6 0.001 Error 24 23.14 Treatment (no) it i Se Grouping“ Dead bamacles (3) 33.00 i 2.10 a Live barnaeles (1) 20.00 $1.85 b Control (4) 18.50i226 b Bare rock (2) 1.33 i 0.71 e "‘ Means with the same Ietter are not significantly different by :1 least significant difference test Predation. Mussels declined during the last twelve wks of the experiment at both sites A and B (Fig. 1), but there Were significant differences between predator removal and predator control areas at both sites at the end of the experi- ment. At site A, for quadrats in which mussels were not removed, mussals were significantly more common (I = 2.37, d.f.=14, p20.006), and bamacles were significantly less Common 0:321, d.f.:14, P=0.006), in the predator re~ moval area. These differences did not exist at the beginning 0f the experiment (mussels: 1:0.74, d.f.= 14, P=0.469; barnacles: I: 0.36, d.f.:14, P: 0.723). The same result was Observed at site B: mussels were significantly more common (I: 6.53; d.f. : 6, P<0.001), and barnacles were significant- ly less common (I = 2.49; d.f. = 6; P: 0.047), in the predator rtttnoval area than in the predator control area. These dif- aErr—noes between areas also did not exist at the beginning of the removal experiment (mussels: 1:029, d.f.=6, P: 0.478; barnacles: 1: 1.78, d.f. = 6, P: 0.171). t 4—_f—" 307 Note that theSe statistical comparisons are between re- moval and control areas, rather than between the treat— ments per se. Unfortunately. because we had only two re- moval and two control areas. we have very little power (scnsu Cohen 1977) to detect differences between treat- ments. Surprisingly. the Manda removal treatment hadn significantly negative effect on mussels nonetheless (FLl i 267, P:0.039), and a positive but non—significant effect on barnacles (FLl 233.14. P=0.109) (see Fig. 1). Crowding urm’ dcsircarimr in homicides. CrOWded barnaelcs showed no signifieanl mortality in response to exposure period. but the survivorship of isolated barnacles was signif- icantly reduced after 6.5 and 7 h of exposure (Table 3). Hence crowding in barnacles seems to have increased the resistance of barnacles to desiccation during summertime low tides. Barnacle-r and mussel recruitment. The recruitment of mus- sels (i.e. the survivorship of colonists to a size observable by the naked eye) was positively affected by the presence of barnacles. Mussel recruitment was highest in treatment (3) where barnacles were killed but not removed (Table 4); this was became of recruitment into. as well as between, the dead barnaele shells. Virtually no mussel recruitment (or survival) was observed in the quadrats of treatment (2) where both barnacles and mussels had been removed (see also Menge 1976). The means of treatments (1) where only mussels were originally removed, and (4) where neither species was removed, were not significantly different from each other. These means, howwer, were significantly lower than the mean of treatment (3), and significantly higher than the mean of treatment (2). Discussion The northern Gulf of California is unique in its strong sea- sonality and therefore useful for testing the generalizations regarding intertidal community structure that have come f rom’less seasonal regions. The present study was concerned with contrasting the effects of desiccation and predation in mediating the effect of mussels on barnacles following an early summer pulse in mussel settlement. Surprisingly, the results indicated no effect of exposure during summertime low tides on the mussel—barnacle com- munity; quadrats that were kept continuously moist during daytime low tides did not differ significantly from untreated control sites. This result differs from some previous studies, in which the vertical ranges of species were increased by experimental trickles of water (Hatton 1938; Frank 1965). The absence of significant differences in our experiment is difficult to interpret with confidence, because it may sim- ply be that we did not keep the experimental quadrats wet enough for colonization by species, which normally live lower in the intertidal; but it does suggest the possibility that such larvae (or spores) are absent during the summer or that they have the additional requirement of shade for summertime colonization. In the spray experiment, we had expected mussels to survive through the summer in sprayed, but not in control, quadrats. The lack of response by mussels may have been due to the capacity of tightly packed barnacles (which char- acterized our sites) to modify the microenvironment. We found that individual barnacles living in contact with con- 308 . —— specifics had a greater (100%) survivorship during exposure by low tides than isolated barnacles. The mechanism for this is potentially two—fold: (1) clumps of barnacles tend to retain more moisture (personal observations). and (2) they are likely to reduce the thermal loading of the rock substrate. This positive effect of barnacles on barnacles is likely to be extended to mussels living within the barnacie clump. It may be for this reason that mussels either actively select barnacles for settlement, or that they have enhanced survivorship among barnacles as juveniles (Dayton 1971; Paine 1974; Menge 1976). The results ofthe present study also suggest that Mortii’a preys selectively on Bi'nr/ria'onft’s, and that this mussel has a negative effect on Chi/JCHTMU'HS in the absence of such pre- dation. Hence Moriiln would seem at least partially respon- sible for the late summer decline in mussels; and it appears to have had an indirect, positive effect on barnacles. In the Month: removal areas at both sites A and B (where mussels were not experimentally removed), mussels were significantly more common and barnacles were significantly less common than in the non-removal areas, differences that did not exist at the beginning of the experiment (Fig. 1). We wish to emphasize, nontheless. that the statisti— cal tests in the Marnie removal experiment are comparisons of physical locations, rather than treatments per se (see (Hurlbert 1984). We have made the connection between physical locations and treatments, because the removal ar— eas diverged from the non-removal areas in both sites dur- ing the course of the experiment, and because, in our view, the simplest explanation for this divergence is that it is the result of removing the predator (see also Stewart-Oaten et al. 1986). Independent evidence for a negative effect of mussels on barnacles in the absence of Manda comes from the ex- perimental removal of mussels from randomly selected quadrats in the Morula removal area at site A. Barnacles were more abundant in the mussel removal quadrats (but the difference was only marginally significant; see Table 2). This result is consistent with previous studies on mussel- barnacle interactions, which have shown that mussels com- ' pete with barnacles in the absence of mussel predators (Dayton 1971; Luckens 1975; Paine 1966a, 1974). Taken together, our results suggest that Morale and Chihamalus might be “indirect mutualists" (sensu Vander- meer 1980). Morula benefits from the presence of Chthama- [us because the latter aids recruitment by muSSels, and Chthamalus benefits from the presence of Momla because Morale selectively removes mussels. Whether they are, in fact, indirect mutualists depends on the direct effect of Mor- ula on bamacles, especially during the fall through spring when mussels are rare. Raimondi (unpublished work) has recently shown that Morula is a switching predator (sensu Murdoch 1969) and that it will eat barnacles when mussels are rare or absent; so the effect of Morula on barnacles is likely to be seasonally dependent, with a variable net effect among years depending on the mussel recruitment. The indirect effects between Morula and the “barnacle spe- cialist,” Aeantht‘na angelica (Paine 1966b) may also be sea- sonally dependent for the same reason. In summary, the gastropod predator, Morula ferrugin- osa, specializes on mussels and this has an indirect and positive effect on bamacles. This is because barnacles facili- tate recruitment by mussels, which overgmw them in the absence of such predation. Crowding by bamacles enhances their survivorship during the summer, but summertime tem- perature extremes appear to have no effect on the mussel- barnaele interaction. A(khan-lactatininIs. We thank M. Carr, .1. Connell. C. DeAntonio, L. Dclph. B. Douros. M. Dungan, D. Lohse, M. McKone, S. Pennings, and R. Rowe for comments on various drafts of the manuscript and K. Mangin and L. Delph for help with the experi- ments. This study was supported by at NSF Pre-Doctoral Fellow- ship and a Sigma Xi Grant-in-Aid of Research to Raimondi, and grants from NAS (Joseph Henry Fund}, The American Museum of Natural History (Lerner—Gray Fund). and Sigma Xi to Lively. References Bertness M D (1981) Predation, physical stress and the organization of a tropical rocky intertidal hermit crab community. Ecology 622411—425 Brusca RC (1980) Common intertidal invertebrates of the Gulf of California (2nd Edition). University of Arizona Press. Tues son, AZ Cohen J (1977) Statistical power analysis for the behavioral sciences. Academic Press, New York Connell JH (1961) Effects of competition, predation by Thais [aptl- lus and other factors on the distribution ofthe barnacle Chihu- malus stellattis, Ecology 42:71k723 Connell JH (1970) A predator-prey system in the marine intertidal region. I. Bairmus glandut'a and several predatory species of Their. Ecol Monogr 40:49—78 Connell JH (1972) Community interactions on marine rocky inter- tidal shores. Ann Rev Ecol Syst 3 : 1694172 Connell JH (1978) Diversity in tropical rain forests and coral reefs. Science 199 : 1 30271310 Connell JH (1983) On the prevalence and relative importance of interspecific competition: evidence from field experiments. Am Natur 122:661—696 Conneli JH (1985) The consequences of variation in initial settle- ment vs post-settlement mortality in rocky intertidal communi- ties. J Exp Mar Biol Ecol 93:11—45 Davidson D, Inouye RS, Brown JH (1984) Granivory in a desert ecosystem: experimental evidence for the facilitation of ants by rodents. Ecology 65: 178041786 Dayton PK (1971) Competition, disturbance and community orga- nization: the provision and subsequent utilization of space in a rocky intertidal community. Ecol Monogr 41 :3514389 Dethier MN, Duggins DO (1984) An “indirect commensatism“ between marine herbivores and the importance of competitive hierarchies. Am Nat 124:205—219 Dungan ML (1985) Competition and the morphology, ecology, and evolution of acorn bamacles: an experimental test. Paleo- biology 11:165—173 . Dungan ML (19863) Three way interactions: barnacles, limpets, and algae in a Sonoran Desert rocky intertidal zone. Am Nat 127:2927316 Dungan ML (1987) Indirect mutualism: complementary effects of grazing and predation in a rocky intertidal community. In: Kerfoot We, Sih A (eds) Predation: direct and indirect impacts on aquatic communities. University Press of New England, Hanover, N.H. pp 188—200 Frank PW (1965) The biodemography of an intertidal snail popula- tion. Ecology 46:831—844 Garrity SD, Levings SC (1981) A predator-prey interaction be— tween two physically and biologically constrained trepical rocky shore gastropods: direct, indirect, and community effects. Ecol Monogr 51 :267—286 Hatton H (1938) Essais de bionomie explicative sur quclques especes intercotidales d‘algues et d‘animaux. Ann Inst Monaco 17:241—348 Hendrickson JR (1973) Study of the marine environment in the northern Gull‘ of California. Nat‘l Tech Info Svc Publ N74- 161108: 1-95 [[urlbcrt SH (1984) Pseudoreplicalion and the design of ecological field experiments. Ecol Monogr 54:187—211 lively CM (198611) Predator-induced shell dimorphism in the acorn hurnaclc ('thmmrfns ruti'sriprni-ia Evolution 40:232—242 | ivcl)’ CM (1986b) Competition, comparative lil‘e histories. and maintenance 01' shell dimorphism in a barnacle. Ecology (171858—8174 |.uhchcnco J (1978) Plant species diversity in a marine intertidal comm unity: importance 01‘ food preference and algal competi- tive abilities. Ant Nut 112:23739 [ uekcns PA (1975) Competition and intertidal zonation of Emma clcs at Leigh, New Zealand. New Zealand .1 Mar Freshwater Res 9: 3797 394 Multisa JR (1986) Life history and environment in two species ul'intertidal barnacles. Biol Bull 170:409—428 :‘vlcngc BA (1976) Organization of the New England rocky intertid- al community: role 01' predation, competition and environmen— tal heterogeneity. Ecol Monogr 46:3557393 Mcnge BA (1978 a) Predation intensity in a rocky intertidal com- munity. Relation between predator foraging activity and envir ronmental harshness. Oecologia (Berlin) 34: 1—16 Mcngc BA (1978 b) Predation intensity in a rocky intertidal come munity. Effect of an algal canopy, wave action and desiccation on predator feeding rates. Oecologia (Berlin) 34:17—35 Mengc BA, Lubchenco J (1981) Community organization in tem- perate and tropical rocky habitats: prey refuges in relation to consumer pressure gradients. Ecol Monogr 51 :429—450 Morin PJ (1983) Predation, competition, and the composition of larval anuran guild. Ecol Monogr 53:119—138 Murdoch WW (1969) Switching in general predators: experiments on predator specificity and stabiiity of prey populations. Ecol Monogr 39:335—354 Paine RT (1966a) Food web complexity and species diversity. Am Nat 100:6?75 Paine RT (1966b) Function of the labial spine, composition of diet, and size of certain marine gastropods. Veliger 9:17—24 Paine RT (1971) A short term experimental investigation of re- fl:% 309 scorce partitioning in a New Zealand rocky intertidal habitat. Ecology 52: 1096—1106 Paine RT (1974) Intertidal community structure: experimental stu- dies on the relationship between a dominant competitor and its principal predator. Occologia (Berlin) 151937120 Sale PF (1977) Maintenance 01‘ high diversity in coral reef fish communities. Am Nat 111:337—359 - Schooner TW (1983) Field experiments on interspecitic competi- tion. Am Nat 12212407285 Sih A. Crowley P. McPeek M. Petranka .l. Strohrneier K (1985) Predation, competition, and prey communities: a review of field experiments. Ann Rev Ecol Syst 16:269—311 Sousa WP (1979) Disturbance in marine intertidal boulder fields; the noncquilibrium maintenance of species diversity. Ecology 60:1225—1239 Sousa WP (1984) The role of disturbance in natural communities. Ann Rev Ecol Syst 15: 353—391 Stewart-Galen A, Murdoch WW, Parker KR (1986) Environmen- tal impact assessment: “pseudoreplication” in time? Ecology 672929—940 Thomson DA (1983) Tide calendar for the northern Gulf of Cali- fornia. Printing and Reproductions, Univ Arizona, Tucson, Ar- izona, USA Thomson DA, Lehner C (1976) Resilience of a rocky intertidal fish community in a physically unstable environment. .1 Exp Mar Biol Ecol 22:1—29 Underwood A], Denley EJ (1984) Paradigms, explanations, and generalizations in models for the structure ofintertidal commu- nities on rocky shores. In: Strong Dr Jr, Simberloff D, AbeIe LG, Thistle AB (eds) Ecological communities: conceptual issues and the evidence. Princeton Univ Press, Princeton, NJ pp 151480 Vandermeer JH (1980) Indirect mutualism: variations on a theme by Stephen Levine. Am Natur 11624-41448 Zar JH (1974) Biostatistical analysis. Prentice-Hall, Englewood Cliffs, NJ Received November 4, 1986 northern Gull‘ of California. Nat‘l Tech Info Svc Publ N74- 161108: 1-95 [[urlbcrt SH (1984) Pseudoreplicalion and the design of ecological field experiments. Ecol Monogr 54:187—211 lively CM (198611) Predator-induced shell dimorphism in the acorn hurnaclc ('thmmrfns ruti'sriprni-ia Evolution 40:232—242 | ivcl)’ CM (1986b) Competition, comparative lil‘e histories. and maintenance 01' shell dimorphism in a barnacle. Ecology (171858—8174 |.uhchcnco J (1978) Plant species diversity in a marine intertidal comm unity: importance 01‘ food preference and algal competi- tive abilities. Ant Nut 112:23739 [ uekcns PA (1975) Competition and intertidal zonation of Emma clcs at Leigh, New Zealand. New Zealand .1 Mar Freshwater Res 9: 3797 394 Multisa JR (1986) Life history and environment in two species ul'intertidal barnacles. Biol Bull 170:409—428 :‘vlcngc BA (1976) Organization of the New England rocky intertid- al community: role 01' predation, competition and environmen— tal heterogeneity. Ecol Monogr 46:3557393 Mcnge BA (1978 a) Predation intensity in a rocky intertidal com- munity. Relation between predator foraging activity and envir ronmental harshness. Oecologia (Berlin) 34: 1—16 Mcngc BA (1978 b) Predation intensity in a rocky intertidal come munity. Effect of an algal canopy, wave action and desiccation on predator feeding rates. Oecologia (Berlin) 34:17—35 Mengc BA, Lubchenco J (1981) Community organization in tem- perate and tropical rocky habitats: prey refuges in relation to consumer pressure gradients. Ecol Monogr 51 :429—450 Morin PJ (1983) Predation, competition, and the composition of larval anuran guild. Ecol Monogr 53:119—138 Murdoch WW (1969) Switching in general predators: experiments on predator specificity and stabiiity of prey populations. Ecol Monogr 39:335—354 Paine RT (1966a) Food web complexity and species diversity. Am Nat 100:6?75 Paine RT (1966b) Function of the labial spine, composition of diet, and size of certain marine gastropods. Veliger 9:17—24 Paine RT (1971) A short term experimental investigation of re- fl:% 309 scorce partitioning in a New Zealand rocky intertidal habitat. Ecology 52: 1096—1106 Paine RT (1974) Intertidal community structure: experimental stu- dies on the relationship between a dominant competitor and its principal predator. Occologia (Berlin) 151937120 Sale PF (1977) Maintenance 01‘ high diversity in coral reef fish communities. Am Nat 111:337—359 - Schooner TW (1983) Field experiments on interspecitic competi- tion. Am Nat 12212407285 Sih A. Crowley P. McPeek M. Petranka .l. Strohrneier K (1985) Predation, competition, and prey communities: a review of field experiments. Ann Rev Ecol Syst 16:269—311 Sousa WP (1979) Disturbance in marine intertidal boulder fields; the noncquilibrium maintenance of species diversity. Ecology 60:1225—1239 Sousa WP (1984) The role of disturbance in natural communities. Ann Rev Ecol Syst 15: 353—391 Stewart-Galen A, Murdoch WW, Parker KR (1986) Environmen- tal impact assessment: “pseudoreplication” in time? Ecology 672929—940 Thomson DA (1983) Tide calendar for the northern Gulf of Cali- fornia. Printing and Reproductions, Univ Arizona, Tucson, Ar- izona, USA Thomson DA, Lehner C (1976) Resilience of a rocky intertidal fish community in a physically unstable environment. .1 Exp Mar Biol Ecol 22:1—29 Underwood A], Denley EJ (1984) Paradigms, explanations, and generalizations in models for the structure ofintertidal commu- nities on rocky shores. In: Strong Dr Jr, Simberloff D, AbeIe LG, Thistle AB (eds) Ecological communities: conceptual issues and the evidence. Princeton Univ Press, Princeton, NJ pp 151480 Vandermeer JH (1980) Indirect mutualism: variations on a theme by Stephen Levine. Am Natur 11624-41448 Zar JH (1974) Biostatistical analysis. Prentice-Hall, Englewood Cliffs, NJ Received November 4, 1986 ...
View Full Document

Page1 / 7

Lively Raimondi reading wk3 - Oecologin (BCELLBALU 987)...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online