GODDARD ET AL.: EL NINO IMPACT ON HETEROBRANCH SEA SLUG RANGES 121 
Remarks: The specimen noted above was most likely pumped into the reservoir as a free- 
swimming veliger larva. Aplysia californica has been reported from as far north as Yaquina Bay 
once before, during the strong 1982-83 El Nino (Pearcy and Schoener 1987). 
Aplysia vaccaria Winckler, 1955. Elkhom Slough, Monterey Bay, California, at least 2 spec¬ 
imens and egg strings, low rocky intertidal, 8 July 2016 (Blue Water Ventures 2016); at least 1 
specimen, “low tide,” 16 May 2018 (Imkitayama 2018a). 
Remarks: Behrens (1991) first reported Aplysia vaccaria from Monterey Bay but did not spec¬ 
ify a precise locality. Therefore the above observations from Elkhom Slough might represent a 
small northward range extension from Monterey, where A. vaccaria was found in December 2014 
(RA, personal observations, for image see <https://www.inaturalist.org/observations/1132630>), 
September and October 2015 (Goddard et al. 2016; BG personal observations, for image see 
<https://www. inaturalist. org/observations/5181629>). 
Aplysia vaccaria is usually found south of the Palos Verdes Peninsula (JG, personal observa¬ 
tions). At Naples, Santa Barbara Co., it appeared briefly in late 2013 and again in late 2014, but 
then appeared in abundance starting in mid-2016, laid egg strings in October 2016 and April, Octo¬ 
ber and November 2017 (JG, personal observations), and has persisted through 2017 (Figure 4). 
20 
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Figure 4. Abundance of the Bulla gouldiana and Aplysia vaccaria in the low rocky intertidal at Naples, Santa 
Barbara, California 2006-2017. 
Berthellina ilisima (Ev. Marcus and Er. Marcus, 1967). Ellwood Mesa Reef, 1 specimen, 
13 m depth, 2 November 2016; 3 specimens, 13 m depth, 11 January 2017 (C. Pierre, personal 
communication to JG, 6 October 2016). Living specimens were held at the Marine Science Insti¬ 
tute, UCSB, and observed by JG, 6 October 2017. Anacapa Is, 1 specimen, intertidal, 22 May 2018 
(Taylor 2018). 
