[3 classes: 15 orders: 27 genera: 40 species]

The name ‘Porifera’ derives from Modern Latin and means, literally, “bearing pores”, referring to the pores that perforate the body wall of these organisms.

Porifera are commonly known as sponges and have the simplest body plans of all multicellular animals, with no tissues or organs. Currently there are 9,452 valid species recognised worldwide, including representatives from both fresh and saltwater habitats (Hooper and van Soest 2002, Van Soest et al. 2012, de Voogd et al. 2021). Most sponges have a unique internal canal system used for circulating water, which is made of a series of progressively finer filters connected by chambers lined with flagellated cells called choanocytes. The phylum is divided into four classes: Calcarea (calcareous sponges), Demospongiae (demosponges), Hexactinellida (glass sponges) and the Homoscleromorpha (homoscleromorphs) (Gazave et al. 2011). Currently, there are 70 valid species recognised in the Puget Trough/Georgia Basin ecoregion (de Voogd et al. 2021), though many species remain undescribed in this cryptic group. Indeed, we estimate as many as 300 to 400 taxa may be present off the coast of British Columbia (Austin, unpubl. 2017). To date, 40 taxa have been documented locally, with all classes but the homoscleromophs confirmed for Galiano Island.

Most sponges are filter feeders that tend to thrive in strong current or wave-swept habitats. In tidal passages along the coast of British Columbia, sponges are often the most conspicuous and abundant sessile invertebrates present (Neil McDaniel, pers. obs.). Given that it is difficult to census the biodiversity found in areas with strong currents, additional species have likely gone undocumented from channels around Galiano Island. The homosceleromoph sponge Oscarella sp., for example, is known to occur in inlets of Vancouver Island and would likely be found in deeper waters around Galiano Island with further search effort. This dataset also includes three undescribed sponge species, which is likely a small percentage of the undescribed species in this region. Indeed, new sponge species are frequently described based on specimens sampled in deeper waters (Reiswig 2018).

The glass sponges Aphrocallistes vastus Schulze, 1886 (cloud sponge) (Fig. 4) and Heterochone calyx (Schulze, 1886) (fingered goblet sponge) form extensive deep-water reefs or bioherms, globally unique to the coasts of western Canada and the USA (Dunham et al. 2018). Glass sponge reefs contribute to the productivity of benthic ecosystems by forming habitat for diverse communities of invertebrates and fish and also play an important role in water filtration and carbon sequestration (Dunham et al. 2018). A total of 19 reef complexes have been mapped throughout the region, covering an area of ~ 12 km² (Dunham et al. 2018). The reef off Galiano Island is one of the largest reefs mapped in the region, supporting dense populations of A. vastus and H. calyx and a high diversity of marine animal species (Chu and Leys 2010, Chu and Leys 2012).

Figure 4.  

Aphrocallistes vastus (cloud sponge) – Photograph by Jackson Chu / Fisheries and Oceans Canada.

Uncertainty regarding sponge diversity primarily results from their cryptic nature, which demands specialised knowledge of their skeletal structures and advanced microscopy techniques to confirm species. Most sponges are characterised by their calcareous or siliceous spicules. The abundance, morphology and arrangement of these spicules, along with the form, texture and colour of the sponge, are used to identify specimens with reference to previously-described species. Austin and Ott (Kozloff 1996) provide keys to 130 intertidal and shallow subtidal species, including ~ 20 calcareous sponges, eight glass sponges and 100 demosponges. Additional regional accounts of Porifera include Lamb and Hanby (2005), Carlton (2007), Harbo (2011), Austin et al. (2013), Austin et al. (2014), Jensen et al. (2018) and Ott et al. (2019). For annotated records of sponges reported for Galiano Island, see supplementary materials (Suppl. material 2).

[3 classes: 13 orders: 42 families: 64 genera: 77 species]

‘Cnidaria’ is the Latinised plural form of the Greek κνίδη (knidē), which means “nettle.”

Cnidaria comprise 12,000 extant invertebrate species which primarily occur in marine environments (WoRMS Editorial Board 2021). The phylum is characterised by the possession of a cell called the cnidocyte, which is used for protection or prey capture. Cnidarians may be polypoid, medusoid or alternate between life stages and are grouped into seven classes: Anthozoa (anemones, soft corals, stony corals and sea fans), Cubozoa (box jellies), Hydrozoa (hydrozoans), Myxozoa (obligate parasites), Polypodiozoa (endocellular parasite), Scyphozoa (true jellyfish) and Staurozoa (stalked jellyfishes) (WoRMS Editorial Board 2021). Nearly 600 cnidarian species are known to occur along the Pacific coast of North America (Cairns et al. 2002), over 200 of which are reported for the coast of British Columbia (Brinckmann-Voss 1996, Brinckmann-Voss and Arai 1997, Sendall 2010, Boutillier and Gillespie 2011). Of these taxa, 77 species are reported in the Galiano Island record.

Cnidarians occur widely throughout the marine environment, with medusae present in pelagic and polyps in benthic habitats. While field identification is reliable in some cases, many taxa, especially hydrozoans, require microscopy for reliable determination. Owing to these limitations, certain groups, including anemones and corals, are well represented in the Galiano Island record, whereas others, such as hydroids and hydrocorals and the smaller scyphozoans, are not. The deeper-dwelling soft corals (gorgonians) are also under-represented due to sampling biases toward shallower waters.

In this dataset, we report the recently-described hydroids Leuckartiara longicalcar Schuchert, 2018 (Fig. 5) and Similiclava nivea Calder, Choong & McDaniel, 2015, the latter of which represents a novel family of athecate hydrozoan (Calder et al. 2015). Notable historical reports include the hydrozoan Aglantha digitale (O. F. Müller, 1776) (pink helmit) and the non-native anemone Diadumene lineata (Verrill, 1869) (striped green sea anemone), both collected from Galiano Island in 1859 by Alexander Agassiz (Agassiz 1862, McMurrich 1921, Konecny and Harley 2019). Finally, reports of the anemone Urticina grebelnyi Sanamyan & Sanamyan, 2006 (e.g. RBCM 986-00197-009) were found to be misidentified as Urticina crassicornis (Müller, 1776) in our review of this dataset. Urticina crassicornis is a European species concept commonly misapplied to U. grebelnyi, which is now recognised in the Northeast Pacific (Sanamyan and Sanamyan 2006).

Figure 5.  

Leuckartiara longicalcar – Photograph by Karolle Wall.

Other reported taxa require further study to resolve their taxonomy. For instance, recent molecular analysis of Aequorea in the Northeast Pacific show they belong to a complex (here reported as Aequorea victoria s. lat.), with many other taxa potentially included within this clade (Henry Choong and Wyatt Patry, pers. comm. 2020). Within Alcyonium, two taxa are recognised in the region, though they have yet to be circumscribed. Euphysa also likely represents a complex, the diversity of which has yet to be determined in our region (Claudia Mills, pers. comm. 2020).

The alternation between polypoid and medusoid generations has historically resulted in a great deal of confusion in the classification of cnidarians. Hydroids, in particular, have received little recent taxonomic attention, with the most substantive revisions dating to Fraser (1937). Modern revisions of hydroid taxonomy are currently underway, led by Dale Calder and Henry Choong. References for Northeast Pacific cnidarians are provided by Fraser (1937), Brinckmann-Voss (1996), Kozloff (1996), Brinckmann-Voss and Arai (1997), Cairns et al. (2002), Wrobel and Mills 2003, Lamb and Hanby (2005), Carlton (2007), Sendall (2010), Boutillier and Gillespie (2011), Harbo (2011), Choong 2015, Jensen et al. 2018 and Calder and Choong (2018). For annotated records of cnidarians reported for Galiano Island, see supplementary materials (Suppl. material 3).

[2 classes: 3 orders: 4 families: 4 genera: 4 species]

‘Ctenophora’ means “comb-bearing”—deriving from the Greek κτείς (kteis), meaning "comb", and -φορος (-fóros), a suffix meaning "carrying”.

Ctenophora (comb jellies) are a phylum of predatory marine invertebrates that are characterised by having eight rows of ciliated plates for locomotion. The phylum is divided into two classes containing 150–200 extant species worldwide (Mills 2017). Around 32 ctenophore species are known to the Pacific coast of North America (Cairns et al. 2002), 13 of which are known within the Salish Sea—though only five or six of these species are relatively common (Claudia Mills, pers. comm. 2021). Four species are reported for Galiano Island, the least common of which is Euplokamis dunlapae Mills, 1987 (Fig. 6). This deep water species is abundant at 250 m depth, but only occasionally occurs above 100 m with mixing of the water column, especially during spring tides (Mackie et al. 1992).

Figure 6.  

Euplokamis dunlapae (oval sea gooseberry) – Photograph by Kathleen Reed.

Most ctenophores are pelagic species, with those most well known occurring near the ocean surface and those less understood found at greater depths. Ctenophores possess sticky cells called colloblasts to capture prey and are are highly diverse in morphology (e.g. egg-shaped cydippids, flat and generally combless platyctenids and large-mouthed beroids). The phylogenetic position of Ctenophora in relation to other phyla is still debated and their taxonomy is in dire need of revision (Dunn et al. 2015, Mills 2017). References for Northeast Pacific ctenophores include Kozloff (1996), Wrobel and Mills (2003), Lamb and Hanby (2005), Carlton (2007), Baldwin (2009d), Harbo (2011) and Jensen et al. (2018). For annotated records of ctenophores reported for Galiano Island, see supplementary materials (Suppl. material 4).

[3 classes: 3 orders: 4 families: 4 genera: 6 species]

‘Nemertea’ is the Modern Latin (plural) form of the Greek νημερτής (Nēmertēs)—the name of a sea nymph.

Nemertea, also known as ribbon worms, are a phylum of soft-bodied and unsegmented invertebrate animals. Over 1,300 extant species, mostly found in marine environments, have been described globally (WoRMS Editorial Board 2021). Traditionally separated into two classes, four classes are now recognised: the Arhynchocoela, Hoplonemertea, Palaeonemertea and Pilidiophora (Strand et al. 2018). The Salish Sea is home to 30 of the 41 nemertean species known to the coast of British Columbia (Baldwin 2010a, GBIF.org 2021). Six of these taxa have been documented for Galiano Island to date.

Most nemerteans live in benthic environments, lurking in crevices beneath stones, shells and at the bases of algae or sessile animals. They are largely predatory or scavenging animals, feeding on annelids, clams and crustaceans, though some are commensalists that live within the mantle cavity of molluscs where they feed on micro-organisms filtered out by their hosts (Ruppert et al. 2004). Sampling nemerteans intertidally is most easily accomplished by flipping stones on the beach or by careful observation at very low tides when they are most likely to be exposed.

The key diagnostic features of Nemertea are proboscis characteristics: for example, whether it is armed or unarmed or split into regions. This makes identification of many species difficult as it requires examination of internal anatomy. Some species, such as Tubulanus sexlineatus (Coe, 1904) (six-lined ribbon worm) (Fig. 7), have distinct colour patterns and can be readily identified in the field. Otherwise, a more complete knowledge of Galiano Island's nemerteans would rely on specialised taxonomic expertise, with a focus on benthic communities. Regional references for Nemertea include: Coe (1901), Coe (1904), Coe (1905), Coe (1944), Kozloff (1996), Lamb and Hanby (2005), Carlton (2007), Baldwin (2010a), Harbo (2011) and Jensen et al. (2018). For annotated records of nemerteans reported for Galiano Island, see supplementary materials (Suppl. material 5).

Figure 7.  

Tubulanus sexlineatus (six-lined ribbon worm) – Photograph by Karolle Wall.

[1 class: 1 order: 2 families: 2 genera: 2 species]

‘Platyhelminthes’ is rooted in the Greek πλατύ (platy), meaning “flat”, and ἑλμινθ- (helminth-), meaning “worm”.

Platyhelminthes (flatworms) are a phylum of dorsoventrally flattened, bilaterally symmetrical invertebrates, most of which are found in marine and freshwater environments (Collins 2017). The phylum includes nearly 13,000 extant marine species (WoRMS Editorial Board 2021), though this estimate does not account for cryptic parasitic species, such as trematodes or flukes, and many taxa remain undescribed. Over 170 species are reported for the coast of British Columbia (Baldwin 2010b), two of which have been reported for Galiano Island to date.

Given the region's high diversity of cryptic free-living and parasitic flatworm species, expert search effort is necessary to gain a comprehensive understanding of this understudied phylum. The larger flatworm species in the order Polycladia are the most likely to be found diving or in intertidal areas. However, even with this more visible group, species identification can be difficult, requiring the fixing, cleaning and sectioning of specimens to examine the microscopic details of copulatory organs and other internal anatomy. Only the largest and most distinctly patterned taxa, such as Eurylepta leoparda Freeman, 1933 (spotted flatworm) (Fig. 8), can easily be identified in the field. Of these more conspicuous taxa, around 10 species are likely to be encountered diving around Galiano Island. Many more species could potentially be documented by taxonomic specialists via searches targeting the more obscure free-living species or fluke, tapeworm and monogenean parasites. Regional taxonomic references for platyhelminthes include Kozloff (1996), Lamb and Hanby (2005), Carlton (2007), Baldwin (2010b) and Jensen et al. (2018). For annotated records of platyhelminthes reported for Galiano Island, see supplementary materials (Suppl. material 6).

Figure 8.  

Eurylepta leoparda (spotted flatworm) – Photograph by Karolle Wall.

[1 class]

The name ‘Chaetognatha’ derives from the Greek χαίτη (khaítē), meaning “bristle”, and γνάθος (gnáthos), meaning “jaw”.

Chaetognatha (arrow worms) are a small phylum of predatory animals, all of which are marine, including 130 extant species in the class Sagittoidea (WoRMS Editorial Board 2021). Though they are not diverse, arrow worms are extremely numerous, representing a major component of marine plankton worldwide. Of the six species of arrow worm known to the Northeast Pacific, four have been sampled in the waters off the coast of British Columbia (Lea 1955, Gardner 1982). Parasagitta elegans (Verrill, 1873) (Fig. 9) is the most abundant species reported from the sheltered inland waters of the Salish Sea (Lea 1955). Eukrohnia hamata (Möbius, 1875) is also known to occur infrequently in inland channels, as an oceanic species that is occasionally borne in by the intrusion of offshore waters (Lea 1955, Gardner 1982). It is not possible to determine chaetognath reports in the Galiano Island record as they are based on dive observations, but studies indicate that, in all likelihood, these observations refer to P. elegans. Sampling by use of plankton tows and microscopic analysis would help confirm the local fauna.

Figure 9.  

Parasagitta elegans (arrow worm) – scanning electron miscroscope micrograph by Elaine Humphrey.

Chaetognaths are active predators, grasping their prey with two sets of rigid hooks located at the sides of the head, hence the common name “bristle-mouth.” These predatory animals are chiefly pelagic, occurring in the open ocean. Appearing like a glass arrow in the water, chaetognaths swim by flexing in the middle of the body, which is supported by a hydrostatic skeleton. The lateral fins on either side of the body appear to aid buoyancy, but are not involved in movement. As few species are present locally, students may disregard more cryptic characteristics and distinguish species by focusing on the arrangement of lateral fins and eye colouration (Lea 1955). For a treatment of British Columbia's chaetognaths, including a set of technical keys, see Wailes (1929), Lea (1955), Bieri (1959), Gardner (1982), Kozloff (1996), Lamb and Hanby (2005) and Carlton (2007) provide additional accounts. For annotated records of chaetognaths reported for Galiano Island, see supplementary materials (Suppl. material 7).

[5 classes: 31 orders: 101 families: 151 genera: 214 species]

'Mollusca' is rooted in the Modern Latin 'mollusca', the neuter plural form of 'molluscus', from 'mollis', meaning “soft”.

With about 49,000 extant species (WoRMS Editorial Board 2021), Mollusca are the second largest phylum after Arthropoda (Rosenberg 2014). The phylum comprises seven extant classes (Haszprunar 2001), five of which are locally represented, including Bivalvia (bivalves), Cephalopoda (cephalopods), Gastropoda (snails and slugs), Polyplacophora (chitons) and Scaphopoda (tusk shells). Over 780 marine species are been identified in British Columbia (Bernard 1967, Baldwin 2009b, Cosgrove 2009, Millen 2012, Forsyth and Harbo 2013, Clark 2020), 214 of which are reported for Galiano Island.

Mollusc inventories have historically been limited by outdated taxonomy and other challenges, leaving much hidden diversity that remains to be discovered in the region. As with other groups, European species concepts have historically been misapplied to Northeast Pacific taxa among Mollusca. One example is the aeolid nudibranch Cuthona pustulata (Alder & Hancock, 1854), originally described from the Northeast Atlantic in 1854. Specimens collected under this name from Porlier Pass off Galiano Island by Sandra Millen in 1982 (RBCM 983-00026-001) have since been described as Zelentia nepunicea Korshunova, Fletcher, Lundin, Picton & Martynov, 2018 (pimpled aeolid, Fig. 10), based on genetic sequencing results (Korshunova et al. 2018). Other novel nudibranch species have also been circumscribed in part based on specimens collected from local waters. One species complex, which was reported as Cadlina luteomarginata MacFarland, 1966 (yellow-rimmed nudibranch) for over 50 years, has since been split into four different species, including C. klasmalmbergi (Klas' yellow-rimmed nudibranch), first collected from Baines Bay on Galiano Island (Korshunova et al. 2020).

Figure 10.  

Zelentia nepunicea (pimpled aeolid) – Photograph by Karin Fletcher.

While many nudibranch species revealed through genetic methods can be determined based on morphology, other cryptic taxa often cannot be reliably identified by morphology alone, requiring molecular analysis for confirmation. Locally occurring genera currently under taxonomic revision include Crepidula Lamarck, 1799 and Vermetus Daudin, 1800. Many more taxonomic issues remain to be resolved in future studies.

The cold, rich waters surrounding Galiano Island are home to many remarkable molluscs, including Enteroctopus dofleini (Wôlker, 1910) (giant Pacific octopus), the largest octopus in the world. The largest chiton in the world, Cryptochiton stelleri (von Middendorff, 1847) (gumboot chiton), is also known to the region and is reported for Galiano Island. Introduced bivalves present around Galiano Island include Magallana gigas (Thunberg, 1793) (Pacific oyster), Mya arenaria Linnaeus, 1758 (soft-shelled clam), Nuttalia obscurata (Reeve, 1857) (purple mahogany clam) and Ruditapes philippinarum (Adams & Reeve, 1850) (Japanese littleneck), all of which are now prolific in the Northeast Pacific. Introduced gastropods present include Batillaria attramentaria (G.B. Sowerby II, 1855) (Japanese false cerith) and Myosotella myosotis (Draparnaud, 1801) (mouse-eared snail).

Species that will likely be uncovered with further search effort include the threatened native Ostrea lurida (Carpenter, 1864) (Olympia oyster) and Penitella penita (Conrad, 1837) (flat-tip piddock). Numerous families of minuscule “micro-molluscs” are entirely unrepresented in the Galiano Island record. A diverse chiton fauna may also be under-represented locally, with 39 species in six families known from the intertidal zone to moderate diving depths (< 30 m) in the Salish Sea (Clark 2020), about two thirds of which (27 spp.) have been documented around Galiano Island to date.

Molluscs were traditionally identified based on shell and other morphological characters. However, modern taxonomic treatments generally rely on genetics in addition to morphology, habitat and host species. Many snails also lay diagnostic egg cases. Regional references for Mollusca include: Bernard (1967), Abbott (1974), Kozloff (1996), Harbo (1997), Harbo et al. (1997), Lamb and Hanby (2005), Carlton (2007), Harbo (2011), and Jensen et al. (2018). Bivalves are treated by Foster (1991), Coan et al. (2000), Huber (2010) and Forsyth and Harbo (2013); cephalopods by Cosgrove (2009) and Cosgrove and McDaniel (2009); chitons by Baldwin (2009b) and Clark (2020); gastropods by Behrens (2004), Behrens and Hermosillo (2005), Millen (2012), Korshunova et al. (2018) and Korshunova et al. (2020); and tusk shells by Carlton (2007). For annotated records of molluscs reported for Galiano Island, see supplementary materials (Suppl. material 8).

[2 classes: 6 orders: 15 families: 39 genera: 46 species]

‘Annelida’ was coined in Modern Latin by the French naturalist Jean-Baptiste Lamarck from the French 'annélide', deriving from 'annelés', meaning “ringed ones” (from the Latin 'anulus', for “little ring”).

Annelida are a large phylum of invertebrates, commonly referred to as ringed or segmented worms, comprising over 13,000 extant species (WoRMS Editorial Board 2021). The majority of known species are found in marine environments, though terrestrial and freshwater annelid diversity is likely underestimated—as is the number of marine species. The phylum is traditionally divided into two classes: Clitellata (earth worms, leeches and brachiobdellids) and Polychaeta (polychaetes) (Ruppert et al. 2004). Based on molecular evidence, Sipuncula (peanut worms) and Echiura (spoon worms) are also nested within this clade (Struck et al. 2007). As the taxonomy has not yet been reorganised, however, Sipuncula reported for Galiano Island are here treated as a separate phylum.

Over 450 polychaete species are reported by Baldwin (2009c) for coastal British Columbia. However, many of these species have been identified based on European concepts now known to represent complexes of morphologically similar but genetically different organisms, including many newly-recognised outside of Europe (Carr et al. 2011). In the greater Salish Sea bioregion, no less than 860 annelid species are currently reported from intertidal areas through shelf depths (Leslie Harris, unpublished data). Once deep water and cryptic species are considered, however, the total number of annelids expected to occur in our waters will likely double. Of these, 46 species are reported to date from Galiano Island.

Annelid life history is exceedingly diverse, exhibiting virtually all feeding modes, including suspension feeding, deposit feeding, scavenging, herbivory, and carnivory. This diversity is mirrored in their pervasive distribution throughout most benthic and pelagic marine environments. Gaps in our knowledge of Galiano Island’s annelid diversity partly reflect the challenges that have historically limited our broader understanding of the region’s diversity. Taxonomists working in the region in the past largely relied on European references and only assigned new names for taxa with strikingly different features. However, the characters defining organisms within this challenging group are often very small and difficult to ascertain without resorting to dissection or microscopic examination. Furthermore, the vast majority of polychaetes lie hidden in bottom sediment or among sessile organisms and are rarely noticed by casual observers. Specialised equipment, such as benthic grabs, dredges, sediment air lifts, plankton tows and settlement plates, are needed to capture more than the few conspicuous species seen by beach-goers and divers.

The majority of taxa reported in this dataset are polychaetes, though a few clitellates are also represented. Many of the names reported reflect the ongoing challenges facing those studying this group. Uncertainty is indicated by older reports, such as Chaetopterus variopedatus (Renier, 1804) and Nereis zonata Malmgren, 1867 (here reported as the Chaetopterus variopedatus complex and Nereis cf zonata), which refer to European concepts in which undescribed native species likely remain hidden. Even conspicuous species, such as tubeworms in the genus Myxicola (Fig. 11), commonly reported as M. aesthetica or M. infundibulum (here listed as Myxicola aff. aesthetica and Myxicola aff. infundibulum), are currently under revision. Many other specimens catalogued in this dataset are not determined past genus as specimens were either unavailable or require further examination in light of recent taxonomic revisions.

Figure 11.  

Myxicola aff. aesthetica (Myxicola sp. A, sensu Leslie Harris, provisional name) – Photograph by Karolle Wall.

Polychaete morphology is highly variable, yet their body plan generally consists of an elongated and segmented body. It is the differentiation of their body into segments and the appendages (gills, parapodia, chaetae, cirri, palps etc.) attached to these segments that enables the morphological classification of families, genera and species. Regional references treating annelids include Berkeley and Berkeley (1948), Berkeley and Berkeley (1952), Berkeley and Berkeley (1962), Berkeley (1967), Berkeley (1968), Banse (1979), Banse (1981), Hobson and Banse 1981, Saphronova (1991), Blake (1994), Blake (1995), Hilbig (1995a), Hilbig (1995b), Kudenov and Harris (1995), Blake (1996a), Blake (1996b), Blake (1996c), Blake (1996d), Blake (1996e), Kozloff (1996), Blake (1997), Hilbig (1997a), Hilbig (1997b), Hilbig (1997c), Blake (2000a), Blake (2000b), Blake (2000c), Blake (2000d), Blake (2000e), Hilbig (2000a), Hilbig (2000b), Hilbig (2000c), Lamb and Hanby (2005), Carlton (2007), Baldwin (2009c), Harbo (2011) and Jensen et al. (2018). For annotated records of annelids reported for Galiano Island, see supplementary materials (Suppl. material 9).

[1 class: 1 order: 1 family: 1 genus: 1 species]

‘Sipuncula’ is the Modern Latin plural form of the genus Sipunculus, based on the Latin 'siphunculus', meaning “small tube.”

Sipuncula (peanut worms) are a small phylum of bilaterally symmetrical, unsegmented marine worms, represented by 150 species worldwide (WoRMS Editorial Board 2021)—though a certain amount of cryptic diversity is understood to remain hidden in the phylum (Hsu et al. 2013). Based on molecular evidence, Sipuncula are now considered to be nested within the phylum Annelida along with Echiura (spoon worms) (Boyle and Rice 2014), yet are here treated as a separate phylum. Eight species of Sipuncula are known to the Northeast Pacific (Carlton 2007), of which one, Golfingia (Golfingia) vulgaris vulgaris (de Blainville, 1827) (Fig. 12), is reported for Galiano Island.

Figure 12.  

Golfingia vulgaris (brown peanut worm) – Photograph by Bernard P. Hanby.

Due to their burrowing habit, sipunculids are obscure organisms easily overlooked by divers and casual beachcombers. Some Sipuncula inhabit rock crevices or similar protected areas, while others are found in sand or mud. With additional search effort, other taxa likely to be uncovered in the waters around Galiano Island include Phascolosoma (Phascolosoma) agassizii Keferstein, 1866 and Themiste (Themiste) pyroides (Chamberlin, 1919). Identification relies on features of the tentacles which tend to be drawn into the body when contracted, hence the common name “peanut worms.” Regional references to the sipunculids can be found in Kozloff (1996), Lamb and Hanby (2005) and Carlton (2007). For annotated records of sipunculids reported for Galiano Island, see supplementary materials (Suppl. material 10).

[3 classes: 7 orders: 32 families: 52 genera: 86 species]

The name ‘Crustacea’ is rooted in the Modern Latin 'crusta', meaning “shell.”

Crustacea are a highly diverse subphylum of Arthropoda that contains over 52,000 described terrestrial, marine and freshwater species (Martin and Davis 2001). This subphylum includes six classes (Martin and Davis 2001), five of which are represented locally: Branchiopoda (fairy shrimp and water fleas); Hexanauplia (barnacles, copepods and tantulocarids); Ichthyostraca (fish lice); Malacostraca (amphipods, crabs, isopods, krill and shrimp); and Ostracoda (seed shrimp). Over 900 marine crustacean species are known to occur in British Columbia (Hart 1931, Cornwall 1970, Gardner and Szabo 1982, Daly and Holmquist 1986, Funk and Hobson 1991, Martin et al. 1996, del Carmen Espinosa-Pérez and Hendrickx 2006, Carlton 2007, Baldwin 2009a, Baldwin 2011, Baldwin 2016, Sieg 2017, Green and Gardiner 2019), 86 of which are reported for Galiano Island.

Many crustaceans are difficult to identify without microscopy, contributing to biases in the local record. Locally, ichthyostracan crustaceans are vastly under-represented and cladocerans and ostracods remain unrepresented to date. As of yet, there are no records of hoplocarids (mantis shrimps), ascothoracids or tantulocarids occurring within British Columbia. The latter two groups will likely be discovered with further investigation; hoplocarids, however, have never been observed north of southern California and are unlikely to occur in the region. Leptostracans are not well described, though at least one species from the genus Nebalia is known to the Northeast Pacific (Martin et al. 1996). Closer examination of subtidal and intertidal eelgrass, algae wrack and the rocky intertidal zone will uncover many unrecorded taxa.

Numerous non-native crustaceans are known to the region, though only one introduced species is currently represented in the Galiano Island record. The introduced Caprella mutica Schurin, 1935 (Japanese skeleton shrimp) (Fig. 13), reported for Galiano Island, is now well established along the coast of British Columbia (Frey et al. 2009). The invasive Carcinus maenas (Linnaeus, 1758) (European green crab) and two tanaids, Leptochelia dubia (Krøyer, 1842) and Zuexo normani (Richardson, 1905), have been found off Vancouver Island, but are not yet known locally. Additionally, the non-native amphipods Ampithoe valida Smith, 1873, Caprella drepanochir Mayer, 1890, Incisocalliope derzhavini (Gurjanova, 1938), Melita nitida S.I. Smith in Verrill, 1873, Monocorophium acherusicum (Costa, 1853), Monocorophium insidiosum (Crawford, 1937) and Jassa slatteryi Conlan, 1990, along with the bay barnacle Amphibalanus improvisus (Darwin, 1854), have all been reported in the Strait of Georgia (Lu et al. 2007, Gartner et al. 2016), but have not yet been reported for Galiano Island.

Figure 13.  

Caprella mutica (Japanese skeleton shrimp) – Photograph by Emily Adamczyk.

References for regionally-occurring marine crustaceans include: amphipods (Baldwin 2009a); barnacles (Cornwall 1970, Baldwin 2016); cladocerans (Green and Gardiner 2019); cumaceans (Hart 1931); decapods (Baldwin 2011, Jensen 2014); copepods (Gardner and Szabo 1982); isopods (del Carmen Espinosa-Pérez and Hendrickx 2006); mysids (Daly and Holmquist 1986); tanaids (Sieg 2017); and krill (Funk and Hobson 1991, Li et al. 2013). General references to marine crustaceans known to the region can also be found in Kozloff (1996), Lamb and Hanby (2005), Carlton (2007), Harbo (2011) and Jensen et al. (2018). For annotated records of crustaceans reported for Galiano Island, see supplementary materials (Suppl. material 11).

[1 class: 1 order: 1 family: 1 genus: 1 species]

‘Entoprocta’ derives from the Greek ἐντός (entos), meaning “inside”, and πρωκτός (prōktos), meaning “anus.”

Entoprocta (nodding-heads) are a small phylum of mainly sessile marine invertebrates that comprises 253 described species worldwide (WoRMS Editorial Board 2021). The phylum was traditionally divided into two orders: the Solitaria and Coloniales. Solitaria included solitary species that usually attach to larger organisms which produce feeding currents, such as sponges, bryozoans, polychaetes, sipunculans and ascidians, and are typically associated with just one or a few host species. Coloniales, by contrast, included colonial species that form crusts on various surfaces. However, the traditional system is no longer followed; instead four families are now recognised (WoRMS Editorial Board 2021). Of the 11 species known to British Columbia (Baldwin 2009e), one species is reported for Galiano Island: Barentsia sp. (Hincks, 1880) (Fig. 14).

Figure 14.  

Barentsia sp. (nodding heads) – Photograph by Bernard P. Hanby.

Entoprocts are filter feeders, trapping small particles in the mucus secreted by their tentacles. An understudied group, they are easily overlooked because of their diminutive size (< 1 mm) and the superficial similarities they share with the Cnidaria and Bryozoa (Ruppert et al. 2004). With further search effort, others are likely to be detected locally.

The body plan of entoprocts consists of a cup-like calyx that bears a ring of ciliated tentacles called ­the lophophore, which is attached on its dorsal surface to the substrate by a long, thin stalk or pedicel. Entoprocta have their anus inside their ring of tentacles, while bryozoans (formally known as the Ectoprocta), have their anus outside of their ring of tentacles. Regionally occurring Entoprocta are treated by Kozloff (1996), Lamb and Hanby (2005), Carlton (2007) and Baldwin (2009e). For annotated records of entroprocts reported for Galiano Island, see supplementary materials (Suppl. material 12).

[1 class: 1 order: 1 family: 1 genus: 1 species]

‘Brachiopoda” is formed of the Ancient Greek βραχίων (brakhíōn), meaning “arm”, and πούς (poús), for “foot”.

Brachiopods (lampshells) are a phylum of shelled marine animals found in intertidal and subtidal waters, represented by over 400 species worldwide (WoRMS Editorial Board 2021). The phylum may be divided into three extant subphyla, including the Craniiformea, Linguliformea and Rhynchonelliformea (WoRMS Editorial Board 2021). Of the seven lampshell species known to British Columbia, only three are expected to occur within the Salish Sea: Laqueus californicus (Koch, 1848), Terebratalia transversa (Sowerby, 1846) and Terebratulina unguicula (Carpenter, 1864). One species, T. transversa (Fig. 15), is known to Galiano Island.

Figure 15.  

Terebratalia transversa (transverse lamp shell) – Photograph by Bernard P. Hanby

Most lampshells live at great depths and are thus seldom encountered. Laqueus californicus is known to occur in mass aggregations (945 m^-2) at depths as deep as 700 m, which is likely why this species has eluded search efforts to date (Tunnicliffe and Wilson 1988). Terebratulina unguicula occurs within the subtidal range sampled; however, this species is notable for inhabiting the extremely low-oxygen waters occurring in some fjords within British Columbia and, thus, may not be expected to occur locally (Tunnicliffe and Wilson 1988).

Traditionally, brachiopods were classified into two major groups, based on whether their valve hinge structures are articulate or inarticulate. Shells are orientated in a dorsal-ventral manner, closely resembling bivalve molluscs, the shells of which are lateral in orientation. Yet, whereas bivalves are symmetrical between valves (valves mirror each other), the plane of symmetry in brachiopods cuts through the middle of their valves (valves do not mirror each other). In contrast to bivalves, brachiopods are also typically attached to the substrate by a stalk. They share their feeding organ, the lophophore, in common with the Bryozoa, Entoprocta and Phoronida. Regional accounts of Brachiopoda include Bernard (1972), Hochberg (1996), Kozloff (1996), Lamb and Hanby (2005), Carlton (2007), Baldwin (2009e), Harbo (2011) and Jensen et al. (2018). For annotated records of lampshells reported for Galiano Island, see supplementary materials (Suppl. material 13).

[2 classes: 3 orders: 13 families: 15 genera: 17 species]

‘Bryozoa’ derives from the Ancient Greek βρύον (brúon), “moss”, and ζῷα (zôia), which means “animals.”

Bryozoans, or ‘moss animals’, are colonial animals that are composed of many connected individuals, globally represented by over 6,000 species (Bock and Gordon 2013, WoRMS Editorial Board 2021). While no recently published lists are available to summarise the regional diversity of this phylum, conservative estimates of British Columbia’s bryozoan diversity falls between 210 and 260 species (Baldwin 2009e, Paige Borrett and Graham Gillespie, pers. comm. 2020). A total of 17 bryozoan species are reported for Galiano Island.

Bryozoans are suspension feeders that grow on substrates such as shells, rocks, algae and seagrasses and are prey to micro-predators, such as worms and small crustaceans and gastropods. As bio-constructors, they are known to increase the available habitat and overall diversity of marine ecosystems, making them an important component of many benthic communities. Nevertheless, bryozoans remain a relatively understudied phylum as they have no direct economic value and are generally small, cryptic and difficult to identify without the use of a microscope. Given their obscurity relative to more prominently studied taxa, the diversity of bryozoans around Galiano Island, as throughout the region, is likely under-reported.

Of the 17 bryozoan species reported for Galiano Island, one is introduced to British Columbia: Schizoporella japonica Ortmann, 1890 (orange ripple bryozoan) (Fig. 16). Native to Japan, S. japonica was described by Powell (1970) as an abundant intertidal organism in the Strait of Georgia, where the species is suspected to have been introduced in the early to mid-1930s along with Magallana gigas. The species has since been found in fouling communities from Morro Bay, California to Prince William Sound, Alaska (Ryland et al. 2014, Gartner et al. 2016).

Figure 16.  

Schizoporella japonica (orange ripple bryozoan) – Photograph by Scott Gilmore.

As aquatic suspension feeders, bryozoans pluck food particles from the surrounding water with a specialised structure called a lophophore. Each individual or zooid is typically protected within a covering of calcium carbonate or chitinous material. The protective features and structure of this covering are polymorphic and used to distinguish species. Bryozoan species and their geographic ranges are often listed in invertebrate identification keys (e.g. Kozloff 1996, Lamb and Hanby 2005, Carlton 2007, Harbo 2011, Jensen et al. 2018). Additional resources are available specific to Vancouver Island (O’Donoghue and O’Donoghue 1923, O’Donoghue and O’Donoghue 1926), certain habitats (e.g. Gartner et al. 2016) and for research cruises spanning the Pacific North American coast (Osburn 1950, Osburn 1952, Osburn 1953). For annotated records of bryozoans reported for Galiano Island, see supplementary materials (Suppl. material 14).

[1 class: 1 order: 1 family: 1 genus: 1 species]

‘Phoronida’ is the plural form of the phylum’s type genus Phoronis, likely derived from the Latin 'Phoronis' (the last name of the mythical Io, priestess of Argos).

Phoronida (horseshoe worms) are a small phylum of soft-bodied filter-feeding marine animals that form upright tubes of chiton to support their bodies. Worldwide the phylum includes two genera, comprising 13 recognised species (WoRMS Editorial Board 2021). Six species are reported for the Northeast Pacific (Carlton 2007), of which one species is known locally: Phoronis ijimai (Oka, 1897) (Fig. 17).

Figure 17.  

Phoronis ijimai (white colonial Phoronid) – Photograph by Karolle Wall.

Phoronids are benthic organisms that occur at depths ranging from the intertidal zone to about 400 m of depth in all oceans and seas throughout the world, except the Antarctic seas (Temereva et al. 2000, Emig 2003). Their larvae are pelagic and feed on plankton, sometimes comprising a large proportion of zooplanktonic biomass (Temereva 2010). Of the six species reported for the region, it is uncertain which may be expected to occur around Galiano Island, though Phoronopsis harmeri (Pixell, 1912) has been reported nearby from the Saanich Inlet (RBCM 976-01136-010). Collections are sparse for this understudied phylum and much doubt surrounds the taxonomy and distributional ecology of the regional fauna. Keys are based on fully developed larval stages, so investigations into this phylum generally entail raising larvae to advanced stages so that they can be reliably compared to illustrations for identification (Johnson and Zimmer 2002). Even then, their determination is usually based on internal anatomy, which often can only be gleaned by examining microscopically thin sections (Carlton 2007). Given the challenges associated with this group, most collections at the Royal British Columbia Museum remain unidentified.

Phoronids are called “horseshoe worms” because the top of their worm-like body contains rows of ciliated tentacles forming a horseshoe shape. This is the lophophore—the feeding organ they share in common with the Brachiopoda, Bryozoa and Entoprocta. References to the phoronids reported for the region may be found in Kozloff (1996), Lamb and Hanby (2005), Carlton (2007), Baldwin (2009e) and Jensen et al. (2018). For annotated records of phoronids reported for Galiano Island, see supplementary materials (Suppl. material 15).

[5 classes: 14 orders: 20 families: 30 genera: 41 species]

‘Echinodermata’ is rooted in the Ancient Greek ἐχῖνος (echīnos), meaning “hedgehog”, and δέρμα (derma), “skin”.

Echinoderms are a phylum of marine invertebrates characterised by tough, spiny skin and radial symmetry, containing over 7,000 recognised species worldwide (WoRMS Editorial Board 2021). The phylum comprises five extant classes (WoRMS Editorial Board 2021), all of which are represented locally. These include Asteroidea (sea stars), Crinoidea (crinoids), Echinoidea (sea urchins and sand dollars), Holothuroidea (sea cucumbers) and Ophiuroidea (brittle stars). Of the 111 echinoderm species known to British Columbia (Lambert 1997, Lambert 2000, Lambert and Austin 2007), 41 species are reported for Galiano Island.

Echinoderms, especially sea stars, are an ecologically important component of the marine fauna of the Northeast Pacific. The term “keystone species” was first coined by Paine (1966) to describe the dominant influence of the predatory Pisaster ochraceus (Brandt, 1835) (ochre sea star) over the structure and composition of intertidal communities. Since 2013, sea stars, such as Pisaster ochraceus and Pycnopodia helianthoides (Brandt, 1835) (sunflower sea star) (Fig. 18), have undergone severe declines in the region due to sea star wasting syndrome and their populations have not yet recovered (Miner et al. 2018). A recent study by Aquino et al. (2021) presents evidence indicating that sea star wasting syndrome may be the consequence of elevated microbial activities induced by high organic matter concentrations, which causes depleted oxygen conditions at the animal-water interface, such that sea stars cannot meet the respiratory oxygen demand of tissues. This phenomenon is likely exacerbated under warmer ocean conditions and anthropogenic nutrient pollution (Aquino et al. 2021).

Figure 18.  

Pycnopodia helianthoides (sunflower star) – Photograph by Karolle Wall.

Under-represented echinoderms in the Galiano Island record include the holothuroids and ophiuroids. This gap is likely due to sampling bias, as many of these taxa are found at deeper depths than have been sampled locally or otherwise tend to be buried beneath rock and sediment. Gaps otherwise relate to limits in taxonomic knowledge. For example, the genus Henricia Gray, 1840 is highly variable and in need of clarification. Genetic studies are underway to sort out many suspected new species of Henricia between Alaska and California, led by the efforts of Roger Clark, Doug Eernisse, ‪Megumi Strathmann and Christopher Mah. Leptasterias hexactis (Stimpson, 1862) also belongs to a species complex (Leptasterias aequalis species complex) requiring further study. Regional accounts of echinoderms include Kyte (1969), Kozloff (1996), Lambert (1997), Lambert (2000), Lamb and Hanby (2005), Carlton (2007), Lambert and Austin (2007), Harbo (2011), Lambert and Boutillier (2011) and Jensen et al. (2018). For annotated records of echinoderms reported for Galiano Island, see supplementary materials (Suppl. material 16).

[1 class: 3 orders: 12 families: 24 genera: 33 species]

The name ‘Tunicata’ comes from the Latin tunicatus, past particle of the verb tunicare, “to clothe with a tunic.”

Tunicates are filter-feeding marine animals that derive their name from their protective exoskeleton, called the tunic, which is formed of proteins and carbohydrates. A subphylum of Chordata, Tunicata are traditionally divided into three classes—Ascidiacea, Thaliacea and Appendicularia—though recent evidence suggests this group is paraphyletic (Delsuc et al. 2018). Ascidiacea, or ascidians, are the most diverse and common class of tunicates and are, indeed, the most well represented class in this dataset. There are around 2,815 described ascidian species worldwide (Shenkar and Swalla 2011). Four of the 71 taxa reported from the coast of British Columbia (Royal British Columbia Museum 2021) are extremely deep-water species, while five are restricted to northern BC and are, thus, not expected for Galiano Island. Of the 62 species that might be expected to occur locally, 33 species have been documented to date.

Ascidians are sessile organisms found at all ocean depths worldwide, attaching to natural surfaces such as rocky outcrops and invertebrate shells, as well as artificial structures such as pilings, docks and boat hulls. Notable reports for Galiano Island include several non-native species that have a long history of invasion, often resulting in measurable impacts in other parts of Canada and around the world (e.g. Lambert 2007, Arsenault et al. 2009, Arens et al. 2011, Zhan et al. 2015). Native to Japan, Botrylloides violaceus Oka, 1927 (lined compound ascidian) (Fig. 19) was first introduced to the Pacific coast in California in 1973 and spread northwards along the coast to Canada (Lambert 2003). Didemnum vexillum Kott, 2002 (carpet sea squirt) is also thought to be native to Japan and was first reported for British Columbian waters in 2003 (Lambert 2009). Other reported taxa, such as Ciona savignyi Herdman, 1882 (sea vase) and Diplosoma listerianum (Milne Edwards, 1841) (grey encrusting compound tunicate), have unknown provenance and may, thus, be described as cryptogenic.

Figure 19.  

Botrylloides violaceus (lined compound ascidian) – Photograph by Jennifer Grant.

Tunicates are generally under-represented in this study as they are easily overlooked; new species are still being discovered in British Columbia (Lambert 2019). The Thaliacea and Appendicularia, in particular, are poorly represented—the former limited to a singular dive observation that has not been identified beyond the level of class and the latter not represented at all. Unlike ascidians, these groups include exclusively pelagic species that are more abundant in warmer waters, with low probability of being detected in surveys around Galiano Island.

Identification of tunicates is often based on gross morphological features, though dissection is occasionally required. Ascidians may be categorised as solitary, social or colonial according to variations on a basic body plan. The individuals, called zooids, are very small (measuring a few mm), but the colonies can be up to several metres large. Though tunicates are generally easily overlooked, often confused with other groups and challenging to identify to species, there are excellent resources available to support their identification, including: popular field guides (Gotshall and Laurent 1980, Lamb and Hanby 2005, Harbo 2011, Jensen et al. 2018); taxonomic keys (Kozloff 1996, Carlton 2007); published journal articles (e.g. Name and Willard 1945, Lambert and Sanamyan 2001, Lambert 2003, Lambert 2019); and online summaries (e.g. Baldwin 2009f, Gartner 2014). For annotated records of tunicates reported for Galiano Island, see supplementary materials (Suppl. material 17).

[11 orders: 29 families: 58 genera: 78 species]

Both Actinopterygii (ray-finned fish) and Chondrichthyes (cartilaginous fish) are treated below.

‘Actinopterygii’ is formed from the Latin 'actino-', “having rays”, and the Ancient Greek πτέρυξ (ptérux), meaning “wings” or “fins.” ‘Chondrichthyes’ comes from the Greek χόνδρος (khóndros), meaning "cartilage", and ἰχθύς (ikhthū́s), meaning "fish".

Actinopterygii contain over 33,000 described taxa and Chondrichthyes (cartilaginous fish) over 1,100 taxa, including both freshwater and marine species (Guinot and Cavin 2016, Weigmann 2016). Over 1,500 marine species are estimated to occur between the Beaufort Sea, Alaska, to the tip of Baja California, Mexico (Milton Love, pers. comm. 2020) and over 400 species reported for Canadian waters in the Northeast Pacific (Peden 2002). To date, 78 species of ray-finned fish and four species of cartilaginous fish have been reported for Galiano Island.

Marine fishes dwell in various habitats, from deep sea (pelagic) to near-shore and intertidal environments. Taxa under-represented in this dataset include chondrichthyes (cartilaginous fish), myxinids (hagfish) and osmerids (smelts). These gaps reflect search efforts mostly biased toward rocky reefs and exposed beach locales, to waters < 30 m in depth. Agonids (poachers), pleuronectids (right-eyed flounders) and zoarcids (eelpouts) are also under-represented. These are primarily subtidal, soft substrate inhabitants, indicating that sampling has been limited in these habitats.

Rockfish, Sebastes G. Cuvier, 1829, are a long-lived and diverse genus of fish in the Northeast Pacific, 11 of which are represented in the Galiano Island record. Species present include the threatened Sebastes maliger (Jordan & Gilbert, 1880) (quillback rockfish) and S. ruberrimus (Cramer, 1895) (yellow-eye rockfish) (Fig. 20), the latter of which is ranked as a species of special concern in Canada (Fisheries and Oceans Canada 2018b). This species may attain large sizes (~ 1 m, 12.6 kg). However, as with other species in the genus, it is slow to mature and reproduce and is, therefore, vulnerable to overfishing and fatality due to barotrauma from catch and release (Rankin et al. 2017). As a consequence, many species of Sebastes are at low levels of abundance in the region (Fisheries and Oceans Canada 2021). Spatially-managed rockfish conservation areas that remain permanently closed to all fishing and extraction activities are vital to ensure their recovery (Rankin et al. 2017).

Figure 20.  

Sebastes ruberrimus (yelloweye rockfish) – Photograph by Don Gordon.

Squalus suckleyi Girard, 1854 (North Pacific spiny dogfish), reported for Galiano Island, is a species of special concern in Canada (COSEWIC 2011). The near-threatened Hexanchus griseus (Bonnaterre, 1788) (bluntnose sixgill shark), is also known from adjacent waters around Mayne Island, BC. This species likely occurs around Galiano Island, though it is not reported in this dataset. One unusual report for Galiano Island is Trachipterus altivelis Kner, 1859 (king-of-the-salmon), an outer coastal species likely represented by a specimen carried in from offshore waters. Introduced fishes, such as Alosa sapidissima (A. Wilson, 1811) (American shad), Salmo salar Linnaeus, 1758 (Atlantic salmon) and Salmo trutta Linnaeus, 1758 (brown trout), are documented from waters not far from Galiano Island, though they have not yet been reported locally. References for the fishes of the Pacific coast of North America include Clemens and Wilby (1961), Hart (1973), Peden (2002), Lamb and Hanby (2005), Love et al. (2005), De Maddalena et al. (2007), Lamb and Edgell (2010), Harbo (2011), Love (2011) and Butler et al. (2012). For annotated records of ray-finned fishes reported for Galiano Island, see supplementary materials (Suppl. material 18).

[3 orders: 3 families: 3 genera: 4 species]

Chondrichthyes are discussed above, alongside Actinopterygii. For annotated records of cartilaginous fishes reported for Galiano Island, see supplementary materials (Suppl. material 19).

[2 orders: 7 families: 12 genera: 13 species]

The name ‘Mammalia’ was coined in 1758 by Linnaeus, from Late Latin (neuter plural) 'mammalis', meaning “of the breast.”

Mammalia are a class of vertebrates containing 6,400 species worldwide (Burgin et al. 2018). Within British Columbia, 31 marine mammal species are represented among two orders, including Carnivora (carnivores) and Cetacea (cetaceans) (Ford 2014). Twenty-two marine mammals have been documented within the Salish Sea, including fifteen cetaceans, five species of pinniped and two mustelids (Ford 2014). Of these taxa, only 12 are known to commonly occur in the region. Thirteen species of marine mammal have been reported in waters around Galiano Island to date.

Among locally occurring cetaceans are: baleen whales, distinguished by their enlarged head containing baleen plates suspended from the upper jaw, their double blowhole and their thick blubber; and toothed whales, distinguished by their teeth and single external blowhole. Certain cetaceans, such as Balaenoptera physalus (Linnaeus, 1758) (fin whale) and Balaenoptera acutorostrata Lacépède, 1804 (common minke whale) have been recorded infrequently in local waters, whereas others, such as Megaptera novaeangliae Borowski, 1781 (humpback whale) and Phocoena phocoeana (Linnaeus, 1758) (harbour porpoise), are commonly seen. Among carnivores, both aquatic pinnipeds, such as Phoca vitulina richardii Gray, 1864 (harbour seal) and semi-aquatic fissipeds, such as Lontra canadensis (Schreber, 1777) (river otter), are represented. Presently, there are no known haulouts of Mirounga angustirostris (Gill, 1866) (northern elephant seal) around Galiano Island, though they are known not far away on Salt Spring Island.

Populations of Eschrichtius robustus (Lilljeborg, 1861) (grey whale), M. novaeangliae, P. phocoena and the southern resident population of Orcinus orca (Linnaeus, 1758) (orca) (Fig. 21) are currently ranked as species of conservation concern in the region (Fisheries and Oceans Canada 2009a, Fisheries and Oceans Canada 2010, Fisheries and Oceans Canada 2013, Fisheries and Oceans Canada 2018a). Northern resident, transient and offshore orcas are also known to traverse local waters and are listed as threatened within Canada (Fisheries and Oceans Canada 2007, Fisheries and Oceans Canada 2009b, Fisheries and Oceans Canada 2018a). Regional accounts of marine mammals include Williams and Thomas (2007), Ford (2014), Nagorsen (2014) and Harvey et al. (2017). For annotated records of mammals reported for Galiano Island, see supplementary materials (Suppl. material 20).

Figure 21.  

Mother (J41) with baby (J51) of the Southern Resident Killer Whale J Pod – Photograph by Karoline Cullen.