Southern California Bight 2003 Regional Monitoring Program: IV. Demersal Fishes and Megabenthic Invertebrates
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- Station (xxxx), Region (a=letter), Shelf zone(a), depth(x-xxx), subshelf(a). Region: C
- Middle Shelf, O
- Abiotic Variable Mapping.
- Species Mapping.
- Species Groupings.
- Nonmetric Multidimensional Scaling.
- Figure VI-16. Stress configurations for nonmetric multidimensional scaling results of site clades of fishes and invertebrates.
| Figure VI-15. Parsimony analysis of endemicity (PAE), or q-mode, cladogram showing the relationships of stations based on their taxa inventories on the southern California shelf and upper slope at depths of 2-476 m, July-October 2003. Brackets on the left identify shelf zones. Brackets on the right identify sub-shelf zones. Larger font size represents majority membership of each bracket. Smaller font size represents minority membership of each bracket. Station Code=Station (xxxx), Region (a=letter), Shelf zone(a), depth(x-xxx), subshelf(a). Region: C=Central, E=Warm (Southeast channel islands), N=Northern, S=Southern, W=Cool (Northwest channel islands). Shelf zone: B=Bays and Harbors, I=Inner Shelf, M=Middle Shelf, O=Outer Shelf, U=Upper Slope. Subshelf: A=Marinas, I=Islands, L=Large POTWs, M=Mainland, N=Mainland non-POTW, P=Ports, S=Small POTWs.
When mapping depth back on to the tree (Figure VI-15) a very clear pattern of assemblages grouping by depth is evident. The basal clades are entirely composed of stations from very shallow depths and generally from bays and harbors. The first 2-12 meter clade is mostly a grouping of samples from San Diego Bay, followed by a 2-7 m clade of primarily Newport Harbor samples with a few San Diego bay samples and a single Marina Del Rey sample. The sister clade “I” is a 6-25 m grouping of a single San Diego sample, followed by shallow Ventura County samples, and the remaining collected from Los Angeles and Long Beach Harbors. The next group or clade, located at the “top” of the cladogram, is also a relatively shallow grouping of samples from 12-34 m with basal components from off San Diego, Long Beach, and the majority collected from the Oxnard and Santa Barbara nearshore areas. The adjacent stations 4094, 4062, and 4064 range from 20-26 m and located off northern and central San Diego County. The next clade is composed of stations from 24-30 m found from San Diego, southern Orange County, and off Long Beach. The sister clade to these stations group slightly deeper stations from southern Orange County to San Diego County in a 36-72 m subclade, with five of seven stations representing small POTWs. The subclade sister to this group is comprised of samples from a similar depth regime, 32-81 m, with smaller groupings exhibiting extreme site or location fidelity, with small sets of stations all from off Newport Beach, Santa Monica bay, and Palos Verdes. This middle-shelf group also contains many large and small POTWs sites. In fact, 43% of these stations are designated as such. The remaining “middle” portion of the cladogram is composed primarily of middle shelf stations. The most-basal sister clade is composed primarily of all “island” stations, with the only exceptions being the two basal stations, 4137 (a 56 m large POTW station located off Newport Beach) and 4019 (located in the Santa Barbara Channel in 84 m). The remaining stations represent a grouping of Channel Island stations that have a tendency for island specific samples to group together. The next clade is a distinct upper slope grouping with station samples ranging from 225-476 m. Once again, not only is there great fidelity with these deep stations grouping together, but many of the sub-groupings, or subclades, are composed of stations all from similar areas. For example, all stations near San Miguel island, stations in the Santa Barbara channel near Point Conception, as well as those deep, more southern stations off San Diego, and the San Pedro Channel group accordingly into their own respective subclades, indicating regional groupings or subdivisions within the more general shelf zone groups. The next group on the cladogram bordered by stations 4349 and 4043, is a shallow inner shelf group composed mainly of stations off Santa Barbara County, with the three basal stations 4208, 4408, and 4158 located in San Diego County, Los Angeles Harbor, and southern Orange County, respectively. This shallow clade is followed by another shallow 12-24 m clade with stations located from as far south as San Diego County to almost Point Conception. The next group has stations located from 29-84 m with a single basal sample (Station 4483) collected at 158 m. This group is composed of stations located off deep northern waters from this survey, as in the case of Station 4483, and then a general grouping of northern middle to inner shelf stations off the Santa Barbara coast as well as a few stations located near San Miguel and Santa Cruz Islands. A small, relatively unresolved (on the cladogram) set of stations, 4323 (152 m), 4285 (198 m), and 4419 (128 m) are all located near each other in the eastern edge of the Santa Barbara Channel. A lone station, 4227 (136 m), is also found in the same area as these three stations in the next clade at a node removed. The next major clade is bordered by stations 4453 and 4006. This is a middle shelf group occurring at depths from 42-86 m. The most apical clade is composed mainly of stations located near large POTWs from 42-76 m. The most apical subclade bordered by stations 4006 to 4141, are all stations in the Santa Monica Bay, proximal to the Hyperion’s 5-Mile Outfall. The base of the next sister clade is composed of stations with large POTW designations, all of which are located off Mission Bay (Station 4036) and Point Loma (Stations 4244 and 4248). The remaining stations are composed of stations located in the Santa Monica Bay or off the Palos Verdes Peninsula, with a single station from off Santa Barbara (Station 4099). The remaining grade of stations, bordered by 4037 and 4453, range from off Malibu (Station 4037) to large and small POTWs off San Diego County (Stations 4120 and 4232), with the 54 m Station 4453 located near Santa Rosa Island. The final large clade of the analysis is composed of a deep (56-110 m) middle shelf group bordered by stations 4027 and 4164, the sister clade or group to the slightly deeper (132-248 m) outer shelf group bordered by Stations 4479 and 4004. The 56-110 m middle shelf group is composed of three basal stations (4164, 4376, and 4184) off Point Loma. With the exception of Station 4086 near the Redondo Canyon, the rest of the clade is composed of stations located in the Santa Barbara Channel near San Miguel, Santa Rosa, and Santa Cruz Islands. The final clade to be discussed is the 132-248 m upper slope clade, the sister group to the 56-100 m middle shelf clade. This group has members located throughout the entire spatial sampling regime from off Point Loma, small subclades of Santa Monica Bay stations, offshore Newport Beach Stations, and a large terminal group of mainly Santa Barbara Channel and Channel Island Stations. Abiotic Variable Mapping. Mapping discrete variables back onto the cladogram in Mesquite 1.05 (Maddison and Maddison 2004) was also conducted to look for geographical patterns relating to regions, shelf, and subshelf zones. Five regions, mainland central, warm southeast Channel Islands, mainland northern, mainland southern, and cool northwest Channel Islands were mapped (but not shown herein due to constraints on color graphics in this report) onto the cladogram (Figure VI-15) as discrete variables. In general, regions were quite distinct within a given clade (stratum or substratum). The bays and harbors clade at the base of the tree broke down into distinct southern versus central subclades. The island clade or stratum was composed of a cool northwest subclade and a warm southeast Channel Island subclade. The very deep (225-476 m) upper slope clade was composed of some southern and central stations in the basal portion of the clade, with all but one station or terminus composed of northern station samples. The 42-76 m middle shelf large POTW clade was composed primarily of central region stations with a southern subclade embedded within. The relatively deep (132-248 m) outer shelf-upper slope clade had many southern components at the base of the clade, followed by many mainland central components, with a terminal clade composed of four mainland northern station samples. Finally, the 24-81 m large POTW clade near the top of the cladogram is mostly composed of mainland central stations with its 36-72 m sister clade composed of all mainland southern stations. The most apical 12-34 m clade has southern and central basal components with the remaining cohorts all composed of mainland northern stations. Five shelf zones, bays and harbors, inner shelf, middle shelf (31-120 m), outer shelf (121-200 m), and upper slope (201-500 m) were mapped onto the cladogram. Very distinct and congruent character mapping clearly distinguished the clades. The basal clades were composed primarily of samples belonging to the bays and harbors shelf zones with two inner shelf stations. The next clade located at the top of the cladogram was composed primarily of inner shelf terminating in middle shelf station samples, with one bay and harbor station. The next clade which is the sister clade to the rest of the cladogram is a middle shelf clade with two outer shelf stations. This is followed by a grade of more middle shelf stations with inner shelf components. The next group is entirely a middle shelf clade which is the sister clade to the shallower 132-248 m outer shelf/upper slope clade. Finally, the deepest upper slope clade, with station depths ranging from 225-476 m, stands alone as the sister clade to the three aforementioned shelf groups. Six subshelf zones, bays and harbors, islands, mainland, mainland non-POTWs, small POTWs, and large-POTWs were mapped onto the cladogram as discrete character states. Again, there is a large degree of subshelf character state distribution and clade fidelity. The bottom grade of stations are primarily bays and harbors with two shallow (12 and 20 m) small POTW stations. The top clades of the cladogram show relatively nested subsets of small POTWs, large POTWs, and non-POTW stations within that group of clades. The rest of the cladogram shows similar patterns of some clades being primarily composed of island stations, mainland stations, and various nested groups of large POTWs, mainland non-POTW, small POTW, and mainland stations. In fact, 65% of the stations found in the most apical set of clades bordered by stations 4094 to 4000 are categorized as either small POTWs or large POTWs, while the other middle shelf group (42-86 m) bordered by stations 4120 and 4006 possesses 67% of the stations categorized mainly as large POTWs. [Note: Portable document format (PDF) files of all mapped variables are available from parsimony analysis section authors Dr. Greg Deets and Curtis Cash (both CLAEMD) at request]. Species Mapping. All 475 taxa were used in the analysis and all taxa were subsequently mapped back onto the cladogram. Character based cladistic methods create testable hypotheses of station relationships in this context, which also yield a highly informative summary of species distributions. Thus, it is the only method in systematics that functions as a general reference classification in biology. In other words, the various species that distinguish certain clades determine the groupings or relationships between the sample stations or strata. Although it is impractical to describe the specific distributions from the character mapping procedure of all of the species, a description of some of the more parsimony-informative distributions follow. The various bay and harbor subclades were held together (minimum of two occurrences) by barred sand bass, California halibut, spotted sand bass, diamond turbot, specklefin midshipman, the sponge Porifera spp. SD4, tuberculate pear crab, shovelnose guitarfish, longstalk sea squirt (Styela montereyensis), cobblestone sea squirt, yellowfin croaker, round stingray, slough anchovy, Pacific calico scallop, black croaker (Cheilotrema saturnum), yellow-green sea squirt, yellow shore crab (Hemigrapsus oregonensis), kelp scallop, Hemphill fileclam (Limaria hemphilli), scaly tunicate (Microcosmus squamiger), warty tunicate, mat mussel, unidentified mussel Mytilus spp., western mud nassa (Nassarius tiarula), California aglaja, unidentified oyster Ostrea spp., California spiny lobster (Panulirus interruptus), and Pacific acorn barnacle. The two aforementioned clades, composed of the many small and large POTW stations, convergently (as they are not sister clades) shared higher occurrences and abundances of California scorpionfish, California tonguefish, brown spiny doris (Acanthodoris brunnea), Pacific argentine, California sand star, roughback sculpin, longfin sanddab, yellowchin sculpin, and gray sand star. The Channel Islands clade and its many smaller subclades are held together by the shared occurrences and increased abundances of red sea urchin (Strongylocentrotus franciscanus), variegate topsnail (Calliostoma variegatum), furrowed rock crab (Cancer branneri), the sea cucumbers Cucumaria piperata and Havelockia benti, blood star (Henricia leviuscula), spotfin sculpin, rock sole, the heart urchin Nacospatangus laevis, spinypalm hermit (Parapagurodes laurentae),slim sculpin (Radulinus asprellus), and banded sea star (Sclerasterias heteropaes). As mentioned above, the deep outer shelf/upper slope station samples grouped into two distinct and somewhat removed clades. A rather deep upper slope clade with station depths ranging from 225-476 m and a shallower outer shelf subclade composed of stations found at depths from 132-248 m. This shallower outer shelf 132-248 m subclade bordered by stations 4004 and 4479 on the cladogram is the sister clade to a 56-110 m middle shelf subclade. It should be noted that of the 27 stations included in this 132-248 m subclade, only two stations, 4329 (228 m) and 4240 (248 m), are significantly deeper than 200 m. The majority of the stations are near 200 m and shallower. Thus, this should be considered an outer shelf clade. This combined middle shelf/outer shelf clade bordered by stations 4004 and 4164 on the cladogram groups together due to the shared occurrences and/or higher abundances of roughdisk brittlestar (Amphichondrius granulatus), the brittlestar Amphiura arcystata, spindle topsnail (Calliostoma turbinum), spotted cusk-eel, Pacific sanddab, moss crab (Loxorhynchus crispatus), gray sand star, moustache bay shrimp, plainfin midshipman, greenstriped rockfish, stripetail rockfish, and shortspine combfish. The stations in the deep 225-476 m upper slope clade, bordered by stations 4039 and 4237 in the cladogram, were grouped together by many species unique or much more abundant in this environment: the anemone Actinostola spp. A, two-tone Amphissa (Amphissa bicolor), sablefish, the turrid Antiplanes thalea, the echiuran Arhynchite californicus, the ophiuroid Asteronyx longifissus, bigeye poacher (Bathyagonus pentacanthus), northern heart urchin, blacktail snailfish (Careproctus melanurus), longhorn decorator crab (Chorilia longipes), Pacific hagfish (Eptatretus stoutii), dogface witch eel, boreopacific armhook squid (Gonatopsis borealis), the seapen Halipteris californica, California smoothtongue (Leuroglossus stilbius), tentacle-shedding anemone (Liponema brevicornis), bigfin eelpout, black eelpout, Pacific hake, the sea star Myxoderma platyacanthum, the echiuran Nellobia eusoma, California grenadier, the ophiuroid Ophiosphalma jolliense, the holothuroid Pannychia moseleyi, filetail catshark, the sea pen Pennatula californica, the sea star Pseudarchaster pusillus, aurora rockfish (Sebastes aurora), shortspine thornyhead, longspine thornyhead (Sebastolobus altivelis), northern lampfish, and signet ring anemone (Stephanauge annularis). These were responsible for this nested topology. Species with relatively restricted (albeit imperfect) distributions or elevated abundances to the outer shelf clade include rex sole, basket star (Gorgonocephalus eucnemis), spotted ratfish (Hydrolagus colliei), threadfin sculpin (Icelinus filamentosus), blackbelly eelpout, slender sole, southern spinyhead, gigantic anemone (Metridium farcimen), smooth western nassa (Nassarius insculptus), gray shrimp, flagnose bay shrimp, bluebarred prickleback, Eastern Pacific bobtail, splitnose rockfish, greenblotched rockfish, blacktip poacher, and shortspine combfish. Incidentally, shortspine combfish was collected in higher numbers and frequency in the Channel Island clade. Species Groupings. The parsimony analysis of co-occurring species (PACOS) resulted in several very similar equally parsimonious trees. Tree number 1 (Appendix D-D13a-d) was randomly chosen to present. In general, species groups derived from the PACOS analysis were amazingly congruent with that found in the recurrent groups analysis, but with larger suites of species as no species are excluded in the analysis and there is not a secondary rationale for species exclusion as determined by the index of affinity in recurrent group analyses. Additionally, PACOS cladograms offer information regarding how widely occurring or how often the various species co-occurred and do so by the relative length of the branches in the cladogram. Being a cladogram, relationships of species groups to other species groups are easily determined via inspection. However, many groups are composed of very unique and somewhat rarely occurring species; hence these will have unresolved relationships (nodes emerging directly from lower levels with neighboring groups. Their apparent closeness on the cladogram should not be confused or interpreted as being closely associated or related in an ecological context. Examining the PACOS cladogram (Appendix D-D13a-d) is probably the easiest way to visualize the fidelity of groupings between this method and recurrent group analysis. Appendix D-D13a and b represents the top half of the cladogram divided up into various subclades of species groupings. Subclade A (Appendix D-D13a) in the upper left hand corner contains recurrent groups 30, 34 and 37; subclade B (Appendix D-13a) contains recurrent groups 25, 35, with Dover sole from recurrent group 41, and California sea cucumber from recurrent group 29. Subclade C (Appendix D-D13b) contains members from recurrent groups 7, 10, 22, 23, 24, 27, 39, 44, 46, and gray sand star from recurrent group 35, and California sea slug from recurrent group 41. Subclade D (Appendix D-D13b) is composed of species from recurrent groups 19, 28, 41, 43, 47, 50, 53, and 54. Subclade F (Appendix D-D13c) contains recurrent groups 3, 4, 6, 9, 16, 51, 52, 55, 57, 58, and 59. Recurrent groups 1, 2, 18, 21, 26, 32, 33, 40, 42, 45, 48 are found in subclade G (Appendix D-D13c). Subclade H (Appendix D-D13d) holds recurrent groups 13, 14, 15, 17, 20, 31, 38, and 60. Finally, subclade I (Appendix D-D13d) consists of many species from recurrent groups 5, 8, 11, 12, 25, 36, and 49. Both the PACOS analysis and recurrent group analysis revealed several subclades of species groups diagnostic of specific ecological strata. Notable examples include subclade B (Appendix D-D13a) with brokenspine brittlestar, plainfin midshipman, stripetail rockfish, a trailtip seapen Acanthoptilum sp, white sea urchin, all from recurrent group 35 and Dover sole a member from recurrent group 41. At the base of this group are several members of recurrent group 25, namely, California blade barnacle, California scorpionfish, bigmouth sole, roughback sculpin, yellow sea twig, and halfbanded rockfish. Other members include Pacific spiny brittlestar (from recurrent group 41), and California sea cucumber (from recurrent group 29). The remaining species, Loebeck's simnia (Neosimnia loebbeckeana) grouping with its specific food source, California sea pen (Virgularia californica), along with mosaic sand star (Luidia armata), fantail sole, and brown spiny doris did not earn recurrent group membership, but enjoy membership in subclade B. The species composing this clade are generally middle and outer shelf inhabitants, but fantail sole is characteristic of the inner shelf. Closely akin to subclade B is subclade E (Appendix D-D13b), represented by California sand star, longfin sanddab, English sole, hornyhead turbot, Pacific sanddab, pink seaperch, longspine combfish, yellowchin sculpin, California tonguefish, New Zealand paperbubble, California lizardfish, and pygmy poacher all belonging to recurrent group 25. Bay goby from recurrent group 29, speckled sanddab from recurrent group 14, and red octopus from recurrent group 41 are also found nested in this clade. Finally, the other species that did not earn recurrent group membership include Pacific argentine, spindle topsnail, pink rockfish (Sebastes eos), Alaska bay shrimp, and California market squid. The aforementioned species found in subclade E are generally common middle shelf inhabitants. The apical portion of subclade D (Appendix D-D13b) contains fragile sea urchin, slender sole, slender blade shrimp, and rex sole all from recurrent group 50; blacktip poacher, moustache bay shrimp, blackbelly eelpout, flagnose bay shrimp, and bluebarred prickleback from recurrent group 47, shortspine combfish from recurrent group 43, and Eastern Pacific bobtail and ridgeback rock shrimp both from recurrent group 41. The remaining species that were not included in any recurrent group membership consist of California king crab, fish-eating star (Stylasterias forreri), gigantic anemone, greenblotched rockfish, southern spinyhead, and bearded eelpout (Lyconema barbatum). All of the species in this clade are known to be members of the outer shelf to upper slope ecosystem. Subclade F (Appendix D-D13c) contains an interesting group composed of offshore blade shrimp, northern heart urchin, orange bigeye octopus, splitnose rockfish, Pacific hake, California heart urchin, sea dandelion, Pacific heart urchin all from recurrent group 51, shortspine thornyhead and bigfin eelpout both from recurrent group 52, dogface witch-eel and California grenadier both from recurrent group 57, and blackbelly dragonfish, bulldog lightfish, and slender hatchetfish all from recurrent group 58. The remaining species not associated with any recurrent groups were aurora rockfish, longhorn decorator crab, the sea pen Halipteris californica, and the wide depth ranging porcelainclaw hermit (Phimochirus californiensis). This group of species represents primarily an upper slope community with some “bleeding” into the outer shelf. The PACOS analysis further identified interesting species subgroups not recognized in the recurrent group effort. For example, subclade G (Appendix D-D13c) contains a small group of species containing a nudibranch Armina sp A, rock sole, the heart urchin Nacospatangus laevis, Santa Barbara spindle (Fusinus barbarensis), spinypalm hermit, fringed sand star (Luidia athenosoma), spotfin sculpin, feather star, curlfin sole, spotted cusk-eel, and orange sand star, which when mapped backed onto the cladogram show a striking propensity to be associated with the Channel Island clade of station samples. Subclade H (Appendix D-D13d) has an interesting group composed of graceful rock crab (Cancer gracilis), purple sea pansy (Renilla koellikeri), Pacific staghorn sculpin (Leptocottus armatus), shiner perch, white seaperch, and Pacific pompano. These co-occurring species represent community members often associated with exposed (high-energy) inner shelf environments. Finally, Subclade I (Appendix D-D13d) with the small group composed of bat ray, channeled nassa (Nassarius fossatus), spotted turbot, and Pacific electric ray, seem to represent another group from shallow mainland areas and the mouths of bays and harbors (albeit the association of bat ray and Pacific electric ray most likely represent an artifactual relationship, due to their wide-ranging and highly mobile life histories). Nonmetric Multidimensional Scaling. Arguably, one of the better ordination techniques is the method of nonmetric multidimensional scaling (NMDS). NMDS was carried out on the patristic distance (branch-length) matrix derived from the cladistic analysis (PAE cladogram). Stress values for the 2-D and the two 3-D (Figure VI-16) configurations were 0.24 and 0.18, respectively. The lower the stress value, the better the correspondence between the NMDS map or plot and the rank order of dissimilarities amongst the samples. Subshelf zones were treated as factors in both of the 2-D and 3-D configurations. In general, like zones grouped together, albeit imperfectly, and the NMDS was able to clearly distinguish the 2 pairs of the highly species rich island stations, represented by the 2 pairs of distant dots on the 2-D NMDS configuration (Figure VI-16). 
Figure VI-16. Stress configurations for nonmetric multidimensional scaling results of site clades of fishes and invertebrates. Directory: pub -> download pub -> Acm word Template for sig site pub -> The german unification, 1815-1870 pub -> Baltic Olympiads in Informatics: Challenges for Training Together pub -> Preparation of Papers for ieee transactions on medical imaging pub -> Forthcoming meetings and conferences pub -> Asilomar Conference on Circuits, Systems & Computers, Pacific Grove, ca, November 1978, pp. 55 58 pub -> Forthcoming meetings and conferences pub -> Harmonised compatibility and sharing conditions for video pmse in the 7 9 ghz frequency band, taking into account radar use Download 11.21 Mb. Share with your friends:
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