Causes of decoupling between larval supply and settlement and consequences for understanding recruitment and population connectivity (2010)

Habitat selection at settlement endures in recruitment time-series (2009)

150 KB

Complexity and simplification in understanding benthic recruitment (2009)

600 KB

Larval transport and dispersal in the coastal ocean and consequences for population connectivity (2007)

1 MB

Stage-specific distribution of barnacle larvae in nearshore waters: potential for limited dispersal and high mortality rates (2007)

1000 KB

Timing of successful settlement: demonstration of a recruitment window in the barnacle Semibalanus balanoides (2006)

100 KB

Barnacle larvae in ice: survival, reproduction, and time to post settlement metamorphosis (2005)

300 KB

Observation of very large and steep internal waves of elevation near the Massachusetts coast (2004)

900 KB

Temperature, stratification and barnacle larval settlement in two Californian sites (2002)

900 KB

Linking larval settlement to larval transport: assumptions, potentials, and pitfalls (2000)

900 KB

Circulation and larval distribution in internal tidal bore warm fronts (1999)

900 KB

Bathymetric species-diversity patterns and boundary constraints on vertical range distribution (1998)

800 KB

Dependence of settlement rate on suitable substrate area (1997)

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Internal tidal bores in the nearshore: warm-water fronts, evidence of seaward gravity currents and the onshore transport of neustonic larvae (1994)

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Spatial and temporal patterns in barnacle settlement rate along a Southern California rocky shore (1994)

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Predictable upwelling and the shoreward transport of planktonic larvae by internal tidal bores (1991)

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OTHER REFERENCES AND PDFs

Predictable upwelling and the shoreward transport of planktonic larvae by internal tidal bores

Jesús Pineda

This paper in a PDF file ( ~460 KB)

Internal tidal bores have a crucial role in the transport of drifting larvae to marine nearshore populations, a key factor in structuring benthic communities. Shoreward transport of larvae and abrupt surface temperature drops lasting days are explained with an hypothesis invoking the advection of subsurface cold water to the shore by internal tidal bores. This process is predictable within the lunar cycle and brings deep water to the surface (upwelling) in a direction perpendicular to the coastline.

1991 Science (Washington D.C.) 253: 548-551          top

Boundary effects on the vertical ranges of deep-sea benthic species

Jesús Pineda

This paper in a PDF file ( ~760 KB)

Since environmental gradients are more pronounced on the continental shelf and continental slope than in deeper waters, it is expected that benthic deep-sea species occurring in shelf and slope regions would have smaller vertical (bathymetric) distributional ranges than species occurring in continental rise and abyssal regions. This paper explains species' vertical range size with a model that considers the existence of boundaries to species vertical distribution (the deepest sea floor and the sea surface). The model assumes that a species' center of distribution corresponds to its mean depth of occurrence [(minimum depth of occurrence + maximum depth of occurrence)/2]. The model shows that the maximum vertical range must be dependent on the mean depth of occurrence. This value peaks at intermediate depths and decreases as one approaches either shallow or abyssal depths; the interaction of the shallow and abyssal boundaries with species' range endpoints produces a constraint envelope that precludes species close to the boundaries from large ranges. Data from different taxa show that there is a relationship between mean depth of occurrence and vertical range for several taxa. Vertical range is small at continental slope (200 - 1500 m) and upper slope depths, increases with depth to a maximum at upper continental rise depths (1500 - 3500 m) and then contracts again at lower continental rise (3500 - 4500 m) and abyssal plain (4500 - 6000 m) depths. Results suggest that boundaries to distribution can have an important effect on the bathymetric gradient of species vertical distributions.

1993 Deep-Sea Research 40: 2179-2192           top

Internal tidal bores in the nearshore: warm-water fronts, evidence of seaward gravity currents and the onshore transport of neustonic larvae

Jesús Pineda

This paper in a PDF file ( ~2 MB)

Nearshore temperature fluctuations are associated with energetic cross-shore two-way flows that influence the onshore transport of neustonic larvae. Water temperature near the surface and bottom at two nearshore stations off southern California (6 and 15 m water depth, respectively) can sharply drop (4 - 7 °C in 6 - 8 h ) and subsequently sharply rise (2 - 8 °C in ca. 0.5 - 2 h). Two or more consecutive rises and drops can occur at diurnal or semidiurnal periodicities. The temperature increases may be accompanied by energetic seaward bottom currents averaging up to 20 cm s^-1 for 1 h together with sharp-edged warm-water fronts visible in surface waters. Shoreward moving fronts divided bodies of water of different surface temperature, where the coldest water body was inshore. Surface water temperature could rise as much as 5 °C in 10 min. Events included one to three fronts that crossed a shallow station and disappeared at (or close to) the surf zone. The sharp drops in water temperature, interpreted as the onshore advection of subsurface water by large internal tidal bores, generate horizontal hydrostatic pressure gradients between the dense inshore surface water and the light offshore surface water. The cross-shore pressure gradients might produce a baroclinic flow, where the density seaward current sets-up, by continuity, the shoreward advection of the light water; onshore warm-water fronts occur concurrently. (In this paper, warm water fronts are defined as linear seasurface features dividing parcels of water of different temperature). It is concluded that sudden increases in temperature and cross-shore advection are epiphenomena of internal tidal bores, a common phenomenon in spring and summer in waters close to La Jolla, California, and they might have similar frequency.

Internal tidal bores have been invoked previously to explain the onshore transport of water - column larvae. This study presents the hypothesis that an epiphenomenon of internal tidal bores also transports neustonic larvae; as a test of the hypothesis that shoreward surface flow transports neustonic larvae in concentrating warm-water fronts, warm-water fronts were identified and neustonic larvae were sampled in fronts and in parcels of water distant from them. Five fronts were sampled in shallow water (about 6 m) for temperature and fish and crab larvae in June - July 1992. These larvae were more abundant in fronts than in parcels of water preceding or following the front. These peaks in larval abundance were accompanied by a sharp rise in temperature, in itself evidence for onshore transport of surface water. It is concluded that both warm-water fronts and internal tidal bores play a key role in the exchange across the shelf of material and water properties, and that internal tidal bore phenomena explain well the transport of larvae in different habitats, water-column and neustonic.

1994 Journal of Marine Research 52: 427-458          top

Spatial and temporal patterns in barnacle settlement rate along a Southern California rocky shore

This paper in a PDF file ( ~1 MB)

Jesús Pineda

Barnacle settlement was monitored at five sites separated by 50 -250 m at Dike Rock, La Jolla, California. Chthamalus spp. and Pollicipes polymerus settlement were spatially correlated at those sites. Within sites, settlement of the two species were correlated with each other. These results support the hypothesis of common onshore larval transport events for all sites and both species. Other spatio-temporal patterns were contrasting: one peak accounted for most of Pollicipes settlement, while there were five peaks of similar magnitude for Chthamalus. At two sites, settlement plates were installed higher and lower in the intertidal. Chthamalus settlement was similar at the two heights; in contrast, Pollicipes settlement was relatively lower at one upper site, but relatively higher at the other upper site. Such spatial patterns might have resulted from a stronger behavioral component at settlement in Pollicipes as compared to the less discriminating Chthamalus. These results suggest that, at scales of 100 m, temporal variability in settlement rate might be related to larval pool and physical transport processes, while spatial variability might be associated with behavioral response and substrate availability.

Chthamalus settlement at Dike Rock was higher at the southern edge of the rocky habitat, on rocks surrounded by unsuitable sandy substrate, possibly because where total suitable settlement area is relatively scarce, settlement rate on available substrate is intensified. To test this, plates were installed at the opposite northern extreme of the rocky shore, where suitable substrate was also scarce. As predicted, settlement was higher at both sites where suitable settlement area was scarce. The hypothesis also explains results obtained at a study site in Medio Camino, Mexico, where settlement became more predictable among sites along the rocky shore after the shoreline had been partially inundated by sand.

The proportion of unmetamorphosed settlers of Chthamalus, relative to total settlement, appeared to peak on particular days of the lunar cycle and was spatially correlated at the five sites. The periodicity of the peaks was close to that of the fortnightly spring-to-neap cycle of 14.75 days. This suggests that peaks in the proportion of unmetamorphosed settlers might be related to periodic short-immersion times that did not allow the attached cyprids to metamorphose. Mortality of recently metamorphosed (< 1 day) Chthamalus spat by physical damage was spatially variable.

1994 Marine Ecology Progress Series 107: 125-138   top

Dependence of settlement rate on suitable substrate area

Jesús Pineda and Hal Caswell

This paper in a PDF file. (Copyright by the Springer-Verlag Society)

Several recent field studies have found disproportionately high settlement rates (expressed on a per- area basis) in situations where the amount of suitable substrate is reduced, either due to the occupation by other individuals or physical processes. We call this phenomenon the intensification effect; it is not included in many models of benthic populations, which assume that the per-area settlement rate is a constant, or in field larval-collector studies, where number of larvae caught is assumed to be a function of only larval supply. In this paper we derive a simple Markov-chain model that generates the intensification effect. It describes the fate of a settling larva, which may be washed out of the system or may attempt to settle in suitable or unsuitable substrate. If it lands on unsuitable substrate, it returns to the water column to try again. At low values of the washout rate, the per-area settlement rate decreases with increasing substrate area. At high values of the washout rate, per-area settlement rate is constant. We conducted a set of experiments with barnacle larvae to illustrate the predictions of the model. Substrate area was manipulated by varying the number of settling panels available, and the larval loss rate was adjusted by manipulating the residence time of the larvae in the experimental units (12 h or 1.5 h). As predicted by the model, in the 12 h treatment settlement per area decreased nonlinearly as the amount of substrate increased, whereas in the 1.5 h treatment no differences were found. These results explain and predict the intensification effect, and suggest that variability in suitable substrate may be an important factor in determining variability in settlement rate.

1997 Marine Biology (Berlin) 129: 541-548           top

Bathymetric species-diversity patterns and boundary constraints on vertical range distribution

Jesús Pineda and Hal Caswell

This paper in a PDF file (807 KB)

A system where a set of species is randomly distributed within two spatial boundaries produces parabolic species diversity patterns, where diversity is lowest in the vicinity of the boundaries, and highest in the mid zone between the boundaries. We demonstrate this phenomenon using simulated data.

We tested whether parabolic depth trends in species diversity (Rex, 1981; 1983) can be explained by invoking only this phenomenon. We analyzed data sets for northwest-Atlantic gastropods and polychaetes previously used to document parabolic diversity patterns. Data sets are matrices of species' abundance where rows index depth, and columns species. Simulations where species vectors were randomly rearranged within the shallowest and deepest stations generally produced parabolic diversity patterns, with higher diversity at intermediate zones, and lowest diversity closest to the shallowest and deepest stations. For the gastropods the location of the peaks for the observed and randomly rearranged taxa coincided at similar depths. Random rearrangements, however, did not match the original patterns in curvature (peakness of the diversity curve) or in magnitude (height of the diversity peak). Highest values were for observed taxa, implying that the original distribution of species is highly non-random, and that other factors not assumed in the simulation influence bathymetric species diversity patterns. For the polychaetes, randomly-rearranged data sets matched the magnitude of the observed data set. The original parabolic diversity curve, however, peaked at a shallower location than the random rearrangements, and the magnitude of the peak was higher for the observed taxa. Overall, we find that the random rearrangements cannot explain most characteristics of the parabolic diversity patterns of gastropods and polychaetes.

We also explored the influence of species with large vertical range in influencing parabolic species diversity patterns. Removal "experiments", where a portion of the species with the largest vertical range was removed, also removed parabolic bathymetric diversity patterns, for both observed and simulated taxa, suggesting that species with large vertical range are disproportionally important in determining such patterns.

1998 Deep-Sea Research II 45: 83-101           top

Circulation and larval distribution in internal tidal bore warm fronts

 Jesús Pineda

This paper in a PDF file (~930 KB)

Internal tidal bore warm fronts were observed during the summer of 1996 off the coast of Southern California. Warm bore fronts had concentrating currents resulting from high-frequency internal motions and from a larger two-way flow; the two-way flow featured surface currents onshore and bottom currents offshore. A sharp thermocline depression and high-frequency, large-amplitude internal motions followed the leading edge of the bore, with downwelling currents on the trailing side of the crest of the nonlinear internal waves and upwelling currents in front of the crest.  *check the bore (~55 kB file)* Warm bores propagated onshore with a propagation speed, c, that ranged from 10.6 to 19.6 cm s^-1, while time-averaged frontal currents, u, varied from 11.2 to 17.6 cm s^-1 in the shallowest bin. In one out of three cases u > c, which implied that there were faster currents than the rate of advance of the front and which implied that the origin of surface frontal material is behind the front, not in front of it. Three invertebrate larval taxa were found at all sites across fronts, but only two intertidal barnacles, Pollicipes polymerus and Chthamalus spp., were concentrated at the front's surface, while the subtidal bryozoan Membranipora spp. was not. Frontal Pollicipes were more concentrated than were Chthamalus. The frontal downwelling currents observed suggested that concentrated larvae would have to swim upward in order to maintain depth. Pollicipes were abundant on the offshore warm side of the fronts but were absent or rare on the onshore colder side, suggesting that the origin of frontal Pollicipes was behind the front, although an alternative cannot be ruled out conclusively. Chthamalus were more abundant at depth than at the surface at all sites except at the front, where this pattern was reversed. The origin of frontal Chthamalus uncertain. Membranipora were more abundant on the onshore colder side of the fronts, and abundances were usually higher at depth than at surface. Lack of accumulation in this species may be due to its limited swimming capability.

1999 Limnology & Oceanography  44:1400-1414         top

Linking larval settlement to larval transport: assumptions, potentials, and pitfalls

 Jesús Pineda

This paper in a PDF file (~918 KB)

Settlement rate time series of nearshore invertebrate taxa can be helpful for posing questions about larval transport processes. However, the potential of these time series remains mostly unexplored, and the assumptions in this inquiring process are rarely identified. This contribution discusses the potentials and pitfalls of using settlement rate time series in posing questions about larval transport. I discuss why physical processes are distinct in the nearshore, up to ~30 m depth, as compared to the offshore, and briefly consider the likely problems in uncritically transferring meso-scale (~100's km) arguments to nearshore discussions. I consider the assumptions of available and shared larval pools often used in shoreward larval transport studies, and then the hierarchical nature of the different processes influencing settlement-rate, developing an argument about their relative importance. Large-scale offshore processes operate first on more larvae than small-scale nearshore processes, which operate last on fewer larvae; it is argued that large-scale offshore processes are disproportionally important in determining population fluctuations. Many field studies using settlement plates or larval collectors assume that settlement rate is only influenced by the rate of arrival of larvae. I discuss how the sampling interval, and the "settlement environment", the background where plates or larval collectors are installed, can influence settlement rate. Settlement often does not correlate directly with larval supply, and settlement interval should be kept as short as possible as settlement and time do not scale proportionally. Finally, I discuss the processes that generate smooth and peaked settlement time series, and the use of settlement time-series in identifying the temporal and spatial scales of physical transport.

2000, in Oceanography of the Eastern Pacific, 1 (2000) 61-81        top

Environmental influences on regional deep-sea species diversity

Lisa A. Levin, Ron J. Etter, Michael A. Rex, Andrew J. Gooday, Craig R. Smith, Jesús Pineda, Carol T. Stuart, Robert R. Hessler, and David Pawson

This paper in a PDF file (~528 KB)

Most of our knowledge of biodiversity and its causes in the deep-sea benthos derives from regional-scale sampling studies of the macrofauna. Improved sampling methods and the expansion of investigations into a wide variety of habitats have revolutionized our understanding of the deep sea. Local species diversity shows clear geographic variation on spatial scales of 100–1000 km. Recent sampling programs have revealed unexpected complexity in community structure at the landscape level that is associated with large-scale oceanographic processes and their environmental consequences. We review the relationships between variation in local species diversity and the regional-scale phenomena of boundary constraints, gradients of productivity, sediment heterogeneity, oxygen availability, hydrodynamic regimes, and catastrophic physical disturbance. We present a conceptual model of how these interdependent environmental factors shape regional-scale variation in local diversity. Local communities in the deep sea may be composed of species that exist as metapopulations whose regional distribution depends on a balance among global-scale, landscape-scale, and small-scale dynamics. Environmental gradients may form geographic patterns of diversity by influencing local processes such as predation, resource partitioning, competitive exclusion, and facilitation that determine species coexistence. The measurement of deep-sea species diversity remains a vital issue in comparing geographic patterns and evaluating their potential causes. Recent assessments of diversity using species accumulation curves with randomly pooled samples confirm the often-disputed claim that the deep sea supports higher diversity than the continental shelf. However, more intensive quantitative sampling is required to fully characterize the diversity of deep-sea sediments, the most extensive habitat on Earth. Once considered to be constant, spatially uniform, and isolated, deep-sea sediments are now recognized as a dynamic, richly textured environment that is inextricably linked to the global biosphere. Regional studies of the last two decades provide the empirical background necessary to formulate and test specific hypotheses of causality by controlled sampling designs and experimental approaches.

2001, in Ann. Rev. Ecol. Syst. 32: 51-93         top

Temperature, stratification and barnacle settlement in two Californian sites

Jesús Pineda and Manuel López

This paper in a PDF file (~879 KB)

Barnacle settlement was monitored in two sites 100 km apart along the coast of Alta and Baja California . In five periods of observations completed between 1991 and 1996, Chthamalus spp., Pollicipes polymerus, and Balanus glandula settlement was consistently higher in the northern site, La Jolla , than in the southern site, La Salina. For Chthamalus, the most abundant settler, settlement was higher in La Jolla in 58 out of 60 paired dates, by a mean factor of 141. In 1996, time series of temperature in about 15 m of water showed that the stratification was 72% higher, on average, and that the thermocline was shallower in La Jolla than in La Salina. Spectra of temperature showed that internal motions of tidal and higher frequencies were more energetic and closer to the surface in La Jolla compared to La Salina. In La Jolla changes in settlement were positively correlated with changes in stratification. These results suggest that high frequency internal motions are important in the onshore transport of larvae. Low-frequency cooling events recorded in La Jolla apparently caused the energetic semidiurnal temperature variability to migrate from the bottom towards the surface, leading to the surface manifestation of the internal tide and surface internal tidal bores, which indicates that the surface nearshore bores occur in response to the shallowing of the thermocline. Tidal and higher frequency internal motions were more energetic when the thermocline was shallow during the low-frequency cooling events, than when it was deep and relatively weak during ordinary conditions. The major cooling event in La Jolla correlated with the local wind, suggesting local wind-driven upwelling. On the other hand, correlation of La Salina temperature with La Jolla temperature, winds, and sea level suggest propagation from the South. These results suggest that the low-frequency drops in temperature that modulate the nearshore internal tidal bores are caused by a combination of the local wind and events that propagate poleward, possibly as coastally-trapped waves.

2002, in Continental Shelf Research, 22: 1183-1198        top

Observation of very large and steep internal waves of elevation near the Massachusetts coast

Alberto Scotti and Jesús Pineda

This paper in a PDF file (~900 KB)

We report on near bottom waves of elevation with amplitude nearly half the 25 m water column, very steep, and propagating into a sheared turbulent wave-guide. The waves contained trapped cores transporting parcels of water shoreward. These large waves depart strongly from weakly-nonlinear and weakly non hydrostatic conditions and challenge established paradigms. They can also represent an important factor in the across-shore transport of plankton and contaminants.

2004, Geophysical Research Letters 31:L22307   top

 

Barnacle larvae in ice: survival, reproduction, and time to post settlement metamorphosis

Jesús Pineda, Claudio DiBacco, and Victoria Starczak

This paper in a PDF file (~300 KB)

Late stage larvae (cyprids) of the barnacle Semibalanus balanoides frequently encounter freezing conditions along the northwest Atlantic coast. S. balanoides cyprids survived for more than 4 weeks embedded in sea ice, and a significant fraction of larvae held in ice up to 2 weeks successfully settled and metamorphosed after thawing. Larvae that completed metamorphosis continued to develop and reproduce. In settlement experiments with cyprids of known age and where settled cyprids were removed every other day from the experimental containers, cyprids held in ice for 2 weeks settled and metamorphosed more than nonfrozen larvae. Mean time to metamorphosis was longer for frozen cyprids than for nonfrozen ones, and maximum time to metamorphosis was 38 d for cyprids held in sea ice for 2 weeks and 26 d for cyprids in nonfrozen treatments. Larval tolerance to freezing conditions greatly expands the environmental tolerance repertoire of marine invertebrates and may help explain the ecological success of this widespread intertidal species.

2005, Limnology & Oceanograpy 50: 1520-1528 top

 

Timing of successful settlement: Demonstration of a recruitment window in the barnacle Semibalanus balanoides

Jesús Pineda, Victoria Starczak and Todd Stueckle

This paper in a PDF file (~100 KB)

Recruitment is a key factor in benthic population dynamics, and spatial and temporal processes that affect settlement may determine recruitment; however, temporal processes are not well understood. We tested whether the date that recruits settle is a random sample within the settlement season by measuring daily settlement of the barnacle Semibalanus balanoides throughout the entire settlement season. A total of 2721 barnacle larvae settled during 89 d on 12 quadrats. Individual settlers were tracked to reproductive age (11 mo after settlement); only 8 survived to reproduction. Survivors settled within a narrow 21 d recruitment window, a period shorter than expected by chance. The concept of a recruitment window has broad implications in studying benthic recruitment and population dynamics. Focus on the recruitment window when it is narrow could simplify the study of recruitment, since fewer factors would have to be considered.

2006, Marine Ecology Progr Ser 320: 233-237 top

 

Stage-specific distribution of barnacle larvae in nearshore waters: potential for limited dispersal and high mortality rates

Fabián Tapia and Jesús Pineda

This paper in a PDF file (~1.3 MB)

The stage-specific spatial distribution and mortality f Balanus glandula and Chthamalus spp. larvae were assessed with a series of daily vertical plankton tows collected from innershelf waters in La Jolla, Southern California, in March 2003. Sampling stations were located within 1.1 km of the shoreline, at depths of 10 to 45 m. For both groups, we observed a spatial segregation of naupliar stages and cyprids, although this pattern was statistically significant for Chthamalus spp. only. Early nauplii (NII and NIII) were more abundant at the inshore stations, whereas later stages (NIV to NVI) occurred in greater numbers offshore. Cyprids were consistently more abundant at the inshore station. Such striking differences in the horizontal distributions of late nauplii and cyprids suggest limited dispersal of barnacle larvae in nearshore waters. Particle trajectories computed from current velocities measured in the area indicated that changes in vertical distribution may indeed affect dispersal, and, in some cases, enhance the retention of larvae in shallow, inner-shelf waters. Vertical life tables were used to estimate naupliar mortality rates from pooled daily stage distributions. Average estimates (±SE) for the instantaneous rate of larval mortality in B. glandula (0.33 ± 0.05 larvae d–1) and Chthamalus spp. (0.23 ± 0.03 larvae d–1) were substantially higher than previously assumed for these species. We discuss the implications of limited dispersal and high mortality rates for the exchange of larvae among disjunct populations of intertidal barnacles and other coastal benthic invertebrates.

2007, Marine Ecology Progr Ser 342: 177-190 top

 

Larval transport and dispersal and consequences for population connectivity

Jesús Pineda, Jon Hare and Sue Sponaugle

This paper in a PDF file (~800 KB)

Many marine species have small, pelagic early life stages. For those species, knowledge of population connectivity requires understanding the origin and trajectories of dispersing eggs and larvae among subpopulations. Researchers have used various terms to describe the movement of eggs and larvae in the marine environment, including larval dispersal, dispersion, drift, export, retention, and larval transport. Though these terms are intuitive and relevant for understanding the spatial dynamics of populations, some may be nonoperational (i.e., not measurable), and the variety of descriptors and approaches used makes studies difficult to compare. Furthermore, the assumptions that underlie some of these concepts are rarely identified and tested. Here, we describe two phenomenologically relevant concepts, larval transport and larval dispersal. These concepts have corresponding operational definitions, are relevant to understanding population connectivity, and have a long history in the literature, although they are sometimes confused and used interchangeably. After defining and discussing larval transport and dispersal, we consider the relative importance of planktonic processes to the overall understanding and measurement of population connectivity. The ideas considered in this contribution are applicable to most benthic and pelagic species that undergo transformations among life stages. In this review, however, we focus on coastal and nearshore benthic invertebrates and fishes.

2007, Oceanography 20: 22-39 top

 

Complexity and simplification in understanding recruitment in benthic populations

Jesús Pineda, Nathalie Reyns and Victoria Starczak

This paper in a PDF file (~600 KB)

Research of complex systems and problems, entities with many dependencies, is often reductionist. The reductionist approach splits systems or problems into different components, and then addresses these components one by one. This approach has been used in the study of recruitment and population dynamics of marine benthic (bottom-dwelling) species. Another approach examines benthic population dynamics by looking at a small set of processes. This approach is statistical or model-oriented. Simplified approaches identify ‘‘macroecological’’ patterns or attempt to identify and model the essential, ‘‘first-order’’ elements of the system. The complexity of the recruitment and population dynamics problems stems from the number of processes that can potentially influence benthic populations, including (1) larval pool dynamics, (2) larval transport, (3) settlement, and (4) post-settlement biotic and abiotic processes, and larval production. Moreover, these processes are non-linear, some interact, and they may operate on disparate scales. This contribution discusses reductionist and simplified approaches to study benthic recruitment and population dynamics of bottom-dwelling marine invertebrates. We first address complexity in two processes known to influence recruitment, larval transport, and postsettlement survival to reproduction, and discuss the difficulty in understanding recruitment by looking at relevant processes individually and in isolation. We then address the simplified approach, which reduces the number of processes and makes the problem manageable. We discuss how simplifications and ‘‘broad-brush first-order approaches’’ may muddle our understanding of recruitment. Lack of empirical determination of the fundamental processes often results in mistaken inferences, and processes and parameters used in some models can bias our view of processes influencing recruitment. We conclude with a discussion on how to reconcile complex and simplified approaches. Although it appears impossible to achieve a full mechanistic understanding of recruitment by studying all components of the problem in isolation, we suggest that knowledge of these components is essential for simplifying and understanding the system beyond probabilistic description and modeling.

2009, Population Ecology  top

 

Habitat selection at settlement endures in recruitment time series

Jonathan Blythe and Jesús Pineda

This paper in a PDF file (~150 KB)

Metamorphosis from a pelagic to a benthic stage is a critical transition in the life cycle of sessile marine invertebrates. The barnacle Semibalanus balanoides attaches permanently during settlement, and once attached, its gross location in the adult habitat is fixed. The partitioning of benthic habitat among barnacles in a recruit cohort is often mediated by settlement timing because early settlement preempts later settlement. We found that barnacles that settled earlier had a higher chance of survival to reproductive age. Additionally, there was a marked preference for some settlement locations over others as indicated by the order that different quadrats were occupied. Location of settlement resolved on a daily timescale over 34 d within 1 site had an enduring influence on which individuals survived to adulthood up to 12 mo later. Furthermore, adult density from a recruit cohort was highly correlated with the timing of settlement. Therefore, habitat selection behavior at settlement may account for a large degree of variability in recruit survival through adulthood in sessile marine invertebrates.

2009, MEPS top

 

Causes of decoupling between larval supply and settlement and consequences for understanding recruitment and population connectivity

Jesús Pineda, Francesca Porri, VIctoria Starczak and Jonathan Blythe

This paper in a PDF file (~300 KB)

Marine broadcast spawners have two-phase life cycles, with pelagic larvae and benthic adults. Larval supply and settlement link these two phases and are crucial for the persistence of marine populations. Mainly due to the complexity in sampling larval supply accurately, many researchers use settlement as a proxy for larval supply. Larval supply is a constraining variable for settlement because, without larval supply, there is no settlement. Larval supply and settlement may not be well correlated, however, and settlement may not consistently estimate larval supply.

   This paper explores the argument that larval supply (i.e., larval abundance near settlement sites) may not relate linearly to settlement. We review the relationship between larval supply and settlement, from estimates and biases in larval supply sampling, to non-behavioral and behavioral components, including small-scale hydrodynamics, competency, gregarious behavior, intensification of settlement, lunar periodicity, predation and cannibalism. Physical and structural processes coupled with behavior, such as small-scale hydrodynamics and intensification of settlement, sometimes result in under- or overestimation of larval supply, where it is predicted from a linear relationship with settlement. Although settlement is a function of larval supply, spatial and temporal processes interact with larval behavior to distort the relationship between larval supply and settlement, and when these distortions act consistently in time and space, they cause biased estimates of larval supply from settlement data.

 Most of the examples discussed here suggest that behavior is the main source of the decoupling between larval supply and settlement because larval behavior affects the vertical distribution of larvae, the response of larvae to hydrodynamics, intensification of settlement, gregariousness, predation and cannibalism. Thus, larval behavior seems to limit broad generalizations on the regulation of settlement by larval supply. Knowledge of the relationship is further hindered by the lack of a well founded theoretical relationship between the two variables. The larval supply–settlement transition may have strong general consequences for population connectivity, since larval supply is a result of larval transport, and settlement constrains recruitment. Thus, measuring larval supply and settlement effectively allows more accurate quantification and understanding of larval transport, recruitment and population connectivity.

2010, JEMBE top

 

Other references

Blythe J, Da Silva JCB, Pineda J (2011) Nearshore, seasonally persistent fronts in sea surface temperature on Red Sea tropical reefs. ICES J Mar Sci 68:1827-1832 PDF

DiBacco C, Fuchs H, Pineda J, Helfrich K (2011) Swimming behavior and velocities of barnacle cyprids in a downwelling flume. Mar Ecol Prog Ser 433:131-148 PDF

Gyory J, Pineda J (2011) High-frequency observations of early-stage larval abundance: Do winter storms trigger synchronous larval release in Semibalanus balanoides? Marine Biology 158:1581–1589 PDF

Starczak VR, Pérez-Brunius P, Levine HE, Gyory J, Pineda J (2011) The role of season and salinity in influencing barnacle distribution in two adjacent coastal mangrove lagoons. Bull Mar Sci 87:275-299 PDF

Davis K, Lentz S, Pineda J, Farrar J, Starczak V, Churchill J (2011) Observations of the thermal environment on Red Sea platform reefs: a heat budget analysis. Coral Reefs 30:25-36 PDF

Magalhaes JM, Araújo IB, Da Silva JCB, Grimshaw R, Davis K, Pineda J (2011) Atmospheric gravity waves in the Red Sea: a new hot-spot. Nonlin Proc Geophys 18:71-79 PDF

Tapia, F., DiBacco, C., Jarrett, J.N., Pineda, J., 2010. Vertical distribution of barnacle larvae at a fixed nearshore station in southern California : stage-specific and diel patterns. Estuar. Coast. Shelf Sci. 86, 265-270. PDF

Scotti A, Beardsley RC, Butman B, Pineda J (2008) Shoaling of nonlinear internal waves in Massachusetts Bay. J Geophys Res 113:18. PDF

Pérez-Brunius, P., M. López, A. Pares-Sierra, and J. Pineda. 2007. Comparison of upwelling indices off Baja California derived from three different wind data sources. CalCOFI Reports 48:204-214. PDF

Cowen, R.K., G. Gawarkiewicz, J. Pineda, S.R. Thorrold, and F.E. Werner. 2007. Population connectivity in marine systems: an overview. Oceanography 20:14-21. PDF

Scotti, A. and J. Pineda (2007). Plankton accumulation and transport in propagating nonlinear internal fronts. Journal of Marine Research 65: 117-145. PDF

Pérez-Brunius, P, M. Lopez M, and J. Pineda (2006) Hydrographic conditions near the coast of northwestern Baja California: 1997 to 2004. Continental Shelf Research 26:885-901. PDF

Ladah, L., F. Tapia F, J. Pineda, and M. Lopez (2005) Spatially heterogeneous, synchronous settlement of Chthamalus spp. larvae in northern Baja California. Marine Ecology Progress Series 302:177-185. PDF

Tapia, F., J. Pineda, F. Ocampo-Torres, H. Fuchs, E. Parnell, P. Montero and S. Ramos (2004). High-frequency observations of wind-forced onshore transport at a coastal site in Baja California. Continental Shelf Research 24, 1573-1585. PDF

Helfrich, K. and J. Pineda. (2003). Accumulation of particles in propagating fronts. Limnology and Oceanography 48: 1509-1520 PDF

Harding, K. C., T. Härkönen, and J. Pineda. 2003. Estimating quasi extinction risk of European harbour seals: reply to Lonergan & Harwood. Ecology Letters 6:894-897. PDF

Pineda J, Riebensahm D, Medeiros-Bergen D (2002) Semibalanus balanoides in winter and spring: larval concentration, settlement, and substrate occupancy. Marine Biology (Berl) 140:789-800. PDF

Sponaugle, S., R. K. Cowen, A. L. Shanks, S. G. Morgan, J. Leis, J. Pineda, G. Boehlert, M. J. Kingsford, K. Lindeman, C. Grimes, and J. L. Munro. 2002. Predicting self-recruitment in marine populations: Biophysical correlates and mechanisms. Bulletin of Marine Science 49:341-375. PDF

Kingsford, M. J., J. Leis, A. L. Shanks, K. Lindeman, S. Morgan, and J. Pineda. 2002. Sensory environments, larval abilities and local self-recruitment. Bulletin of Marine Science 49:309-340. PDF

Levin, L.A., R.J. Etter, M.A. Rex, A.J. Gooday, C.R. Smith, J. Pineda, C.T. Stuart, R.R. Hessler, and D. Pawson. 2001. Environmental influences on regional deep-sea species diversity. Annual Review of Ecology and Systematics 32:51-93. PDF

Souza, A. and J. Pineda. 2001. Tidal mixing modulation of sea surface temperature and diatom abundance in Southern California. Continental Shelf Research 21: 651-666. PDF

Pineda, J. 1995. An internal tidal bore regime at nearshore stations along western USA: predictable upwelling within the lunar cycle. Continental Shelf Research 15:1023-1041. PDF

Pineda, J. 1993. Boundary effects on the vertical ranges of deep-sea benthic species. Deep-Sea Research 40: 2179-2192. PDF

Marquet P., M. J. Fortin, J. Pineda, D.O. Wallin, J. Clark, Y. Wu, S. Bollens, C. Jacobi and R.D. Holt (1993) Ecological and evolutionary consequences of patchiness: a marine-terrestrial perspective. Pp. 277-304 In: Patch Dynamics, S. Levin, T. Powell and J. H. Steele, editors, Springer-Verlag, Berlin. PDF

Pineda, J. (1992). Mareas internas y transporte larvario. Investigación y Ciencia 287 44-45 (Spanish edition of Scientific American).

Pineda, J. and A. Escofet (1989). Selective effects of disturbance on populations of sea anemones from northern Baja California, Mexico. Marine Ecology Progress Series 55: 55-62. PDF