Using light traps to assess larval fish and octopus paralarvae diversity and ontogenetic structure around Santa Catalina Island, CA

Monitoring planktonic larvae is important for understanding changes in recruitment, range shifts, and reproductive behavior. Here, we used light traps to examine the abundance, community diversity, and ontogenetic structure of ichthyoplankton and octopus paralarvae at three sites around Santa Catalina Island, California, USA across two seasons between 2018 and 2019. We identified 15,919 fish larvae and 205 octopus paralarvae using morphology supplemented by DNA barcoding. We found no differences in larval fish diversity or abundance between years or seasons. All octopus paralarvae were captured in the summer and were identified as Octopus bimaculatus. Cryptic substrate-associated fishes dominated samples, especially those from suborder Blennioidei and family Gobiidae. We conclude that light traps can be a valuable tool and useful supplement to other zooplankton sampling methods, especially in providing a more complete assessment of nearshore plankton communities and taxa which have been..., Sampling was conducted from July 7-25, 2018, March 6-10, 2019, and June 6-July 21, 2019. Samples were collected at three coves around Catalina Island, USA: Big Fisherman’s Cove (33.4425, -118.5033), Catalina “Cat” Harbor (33.4345, -118.5033), and Two Harbors (33.4425, -118.4975). At each site, we sampled zooplankton using custom-built cylindrical light traps modeled after Sponaugle & Cowen (1996). Traps were made from 505 μm mesh and measured 30 x 60 cm. To attract zooplankton, we hung a high-intensity 4 LED white dive light (Tektite Mark III) inside the trap. Traps were deployed in the evenings between 17:00 and 20:00 and collected the following morning after a soak time of 12-14 hours. Traps were deployed 1-4 m below the surface. To remove any potential effect of the traps themselves, we rotated which trap was used at each site every night. Within 1 hour of retrieval, traps were washed down with fresh water, transferring zooplankton into an attached 1L cod end. Zooplankton we..., , # Using light traps to assess larval fish and octopus paralarvae diversity and ontogenetic structure around Santa Catalina Island, CA

[https://doi.org/10.7291/D1S38T](https://doi.org/10.7291/D1S38T)

## Description of the data and file structure

Ichthyoplankton records from three sites around Santa Catalina Island, CA

### Files and variables

#### File: Dale_Catalina_Ichthyoplankton_Dryad.csv

**Description:** Larval fish identifications with sample, taxon, and flexion stage information, along with details about sample (date, location). NA values in species and genus columns indicate individuals for which species- or genus-level identifications were not possible.

##### Variables

* sample: Unique ID for each plankton sample, comprised of site code and a value. CH = Cat Harbor, TH = Two Harbors, BFC = Big Fisherman's Cove
* site_name: Name of sampling site around Catalina (Big Fisherman's Cove, Cat Harbor or Two Harbors)
* grouping: General taxonomic grouping according to the most pr...,