Supplementary Material Age validation of yellowfin (Thunnus albacares) and bigeye (T. obesus) tuna of the northwestern Atlantic

Ocean by Andrews, Pacicco, Allman, Falterman, Lang, and Golet. 2019. CJFAS (doi...)

Table S1. Fish and otolith information with corresponding carbon data for juvenile yellowfin tuna (Thunnus

albacares) aged as yearlings (age 1+) with an assumed birth date of 1 January of the previous year on the basis

of margin type (thick translucent) and the 1-year-old yardstick (Lang et al. 2017) — this estimate of a birthdate

is arbitrary and strictly related to the prevention of artificially inflated or deflated ages for individuals with

actual birthdates close to the mean birthdate (e.g. 1 July), which leads to a trivial date-of-formation uncertainty

of a few months and has no effect on the overall birthyear-to-decline relationship. These fish are separated

from the others because age is far less in question (age uncertainty of less than ±3 months) and can be used as

reference points in the bomb 14C decline relationship to provide an indication of what to expect from cored

adult fish otoliths. These specimens were from either the Panama City Laboratory (PC) or the Louisiana

Department of Wildlife and Fisheries (LA) and the age was determined by experienced age readers using a

well-established protocol (Lang et al. 2017).

Sample

number*

Lab number Capture

date

Age

(years)

Straight

FL (mm)

Sex Otolith

mass (g)

F14C

± 2SD

13C

(‰)

YFT-R03 PC 30-44 14-Jul-12 1.5 673 F 0.0210 1.0573 ± 0.0031 –9.7

YFT-R04 PC 27-120 26-Sep-12 1.7 775 M 0.0256 1.0570 ± 0.0022 –10.7

YFT-R05 PC 39-141 24-Oct-13 1.8 n.a. M 0.0216 1.0648 ± 0.0022 –9.9

YFT-R06 PC 62-16 2-Jun-13 1.4 820 F 0.0250 1.0638 ± 0.0028 –9.9

YFT-R07 PC 3-13 25-May-14 1.4 825 F 0.0249 1.0510 ± 0.0036 –9.9

YFT-R09 LA 1094 18-Jun-13 1.5 710 F 0.0192 1.0584 ± 0.0022 –8.7

YFT-R10 LA 248 11-Sep-15 1.7 670 F n.a. 1.0476 ± 0.0021 –9.2

YFT-R11 LA 318 7-Dec-16 1.9 730 M 0.0235 1.0586 ± 0.0030 –9.5

* YFT-R01, R02, and R08 were older than 1 year and later not considered reference material (Table S2).

n.a. = Data not available, not measured, or compromised in some manner.

Table S2. Fish and otolith information with corresponding carbon data for older yellowfin tuna (Thunnus

albacares) used in comparison to the bomb 14C decline relationship (Figs. 2, 3). Specimens were from Panama

City Laboratory (PC) or Louisiana Department of Wildlife and Fisheries (LA) and were aged using the

protocol defined by section images (Fig. 1).

Sample number

Lab number

Capturedate

Age(years)†

Straight FL (mm)

Sex Otolith mass (g)

F14C± 2SD

13C(‰)

YFT-R01* PC 17-1 11-Jun-11 2 1250 M 0.040 1.0627 ± 0.0021 –8.4YFT-R02* PC 26-227 23-Jun-11 3 1310 M 0.052 1.0676 ± 0.0030 –9.5YFT-R08* PC 26-251 10-Aug-14 3 1030 M 0.031 1.0585 ± 0.0022 –10.0YFT-C01 PC 31-51 15-Jul-12 2 1029 F 0.039 1.0541 ± 0.0020 –9.7YFT-C02 PC 30-50 14-Jul-12 2 1086 M 0.040 1.0577 ± 0.0042 –9.6YFT-C03 PC 32-6 1-Jun-12 3 1213 M 0.053 1.0647 ± 0.0023 –9.3YFT-C04 PC 32-5 1-Jun-12 3 1213 F 0.058 1.0598 ± 0.0023 –9.0YFT-C05 PC 64-433 3-Mar-12 4 1380 M 0.067 1.0698 ± 0.0025 –9.2YFT-C06 PC 85-502 20-Jun-12 4 1330 F 0.069 1.0706 ± 0.0024 –8.7YFT-C07 PC 82-573 17-Jun-12 5 1490 M 0.101 1.0770 ± 0.0021 –8.2YFT-C08 PC 51-35 30-Jun-12 5‡ 1530 F 0.103 1.0812 ± 0.0023 –8.6YFT-C10 PC 69-371 9-Mar-12 6 1450 M 0.081 1.0724 ± 0.0024 –9.1YFT-C11 PC 71-123 21-Mar-12 7 1410 F 0.082 1.0713 ± 0.0025 –8.8YFT-C12 PC 28-131 27-Sep-12 7 1511 M 0.092 1.0722 ± 0.0023 –9.5YFT-C13 PC 81-561 16-Jun-12 8 1540 M 0.103 1.0769 ± 0.0025 –9.1YFT-C14 PC 69-340 9-Mar-12 8 1570 M 0.140 1.0793 ± 0.0025 –8.5YFT-C15 PC 78-531 11-Jun-12 9 1390 F 0.104 1.0837 ± 0.0023 –8.7YFT-C16 PC 27-115 26-Sep-12 9 1619 M 0.131 1.0812 ± 0.0022 –8.8YFT-C17 PC 79-533 12-Jun-12 9 1580 M 0.148 1.0762 ± 0.0023 –9.4YFT-C18 PC 28-130 27-Sep-12 10 1543 F 0.117 1.0822 ± 0.0025 –9.2YFT-C19 PC 27-116 26-Sep-12 11 1689 M 0.116 1.0901 ± 0.0027 –8.8YFT-C20 PC 83-581 18-Jun-12 11 1420 F 0.118 1.0898 ± 0.0024 –9.5YFT-C21 PC 45-136 9-Oct-12 12 1664 M 0.106 1.0799 ± 0.0024 –9.4YFT-C22 PC 71-119 21-Mar-12 13 1500 F 0.155 1.0935 ± 0.0024 –9.5YFT-C23 PC 35-68 28-Jul-12 16 1562 M 0.160 1.0956 ± 0.0027 –9.2YFT-C24 PC 66-446 6-Mar-12 17 1390 F 0.127§ 1.1009 ± 0.0030 –9.1YFT-C25 PC 46-2 22-Apr-11 6‡ 1380 n.a. 0.137 1.0717 ± 0.0023 –9.5YFT-C27 PC 26-354 23-Jun-11 10 1570 M 0.127 1.0832 ± 0.0023 –8.4YFT-C29 PC 81-563 16-Jun-12 11 1410 F 0.115 1.0817 ± 0.0021 –9.7YFT-C30 PC 32-15 1-Jun-12 11 1607 M 0.128 1.0892 ± 0.0022 –9.5YFT-C31 PC 61-1 18-May-13 16 1570 F 0.152 1.0937 ± 0.0024 –9.0YFT-C32 PC 31-343 11-Sep-14 18 1810 M 0.183 1.0889 ± 0.0024 –8.7YFT-C33 PC 28-133 27-Sep-12 16 1689 M  n.a. 1.1004 ± 0.0027 –9.2YFT-C34 PC 61-4 18-May-13 18 1640 M 0.133 1.0961 ± 0.0022 –9.7

* YFT-R01, R02, and R08 were older than 1 year and later not considered reference material.n.a. = Data not available, not measured, or compromised in some manner.† Age based on growth zone counts with birth date plotted as difference from collection date.‡ Age reassessed based on offset from decline relationship along with greater than expected otolith mass for the original estimated age (YFT-C08 was unchanged; YFT-C25, changed from 9 to 6 years).

§ Otolith had an unusual shape and lower mass than fish with similar ages.

Table S3. Fish and otolith information with corresponding carbon data for adult bigeye tuna (Thunnus obesus)

used as in comparison to the bomb 14C decline relationship (Fig. 3). Specimens were from Panama City

Laboratory (PC) or Louisiana Department of Wildlife and Fisheries (LA) and were aged using the protocol

defined in section images (Fig. 1).

Sample

number

Lab

number

Capture

date

Age

(years)†

Straight

FL (mm)

Sex Otolith

mass (g)

F14C

± 2SD

13C

(‰)

BET-C01 PC 1-1 15-Jul-11 5‡ 1280 n.a. 0.0837 1.0799 ± 0.0026 –8.8

BET-C02 PC 2-1 22-Jun-12 8 1706 n.a. 0.1007 1.0705 ± 0.0029 –9.0

BET-C03 PC 5-16 1-Jun-12 17 1626 M 0.1762 1.0995 ± 0.0023 –9.2

BET-C04 PC 3-1 15-Jul-12 7 1549 n.a. 0.0972 1.0720 ± 0.0026 –8.7

BET-C05 PC 1-1 29-Jun-12 7 1630 M 0.1033 1.0716 ± 0.0023 –8.8

BET-C06 PC 1-110 1-Sep-13 3 1320 F 0.0579 1.0670 ± 0.0025 –8.3

BET-C07 PC 1000-1 11-Jul-15 4 1281 n.a. 0.0759 1.0607 ± 0.0025 –8.8

BET-C08 PC 1002-1 12-Jul-15 4 1502 n.a. 0.0808 1.0616 ± 0.0020 –9.4

BET-C09 PC 1001-2 26-Jun-15 8 1750 M 0.1070 1.0690 ± 0.0026 –8.9

BET-C10 PC 1000-1 25-Jun-16 12‡ 1705 F 0.1165 1.0656 ± 0.0022 –8.8

BET-C11 LA 620 9-Oct-13 12 1570 n.a. 0.1414 1.0824 ± 0.0029 –9.1

BET-C12 LA 1 12-Dec-18 11 1670 M 0.1292 1.0642 ± 0.0025 –9.0

n.a. = Data not available, not measured, or compromised in some manner.

† Age based on growth zone counts with birth date plotted as difference from collection date.

‡ Age was reassessed based on offset from decline relationship and slightly anomalous otolith mass from what was expected.

(BET-C01 changed from 4 to 5 years; BET-C10 was unchanged).

Fig. S1. Whole otolith mass to

estimated age for YFT and BET. This

relation can often be used as a tool for

eliminating outliers (inconsistent age

reading) and as a rough proxy for age

when selecting a series of specimens

for bomb 14C analyses. Each species

had a positive relationship where the

most massive otoliths were typically

from the oldest fish.

Fig. S2. Whole otoliths of yellowfin

tuna (Thunnus albacares) in reflected

(A) and transmitted (B) light with a

close up of the nuclear region (C).

This figure provides a visual on the

guidelines used to extract otolith cores

from both species — bigeye tuna (T.

obesus) had a very similar otolith

growth configuration. To isolate the

target area, the knob on the distal

surface was removed, followed by a

manual extraction of a targeted area around the otolith nucleus (primordium). The nuclear region was

estimated to be several months of growth. Note that several daily increments are visible near the nucleus

of the targeted area (small bubble is behind and to the right of the nucleus), which could be quantified in

some awkward microscopic views (manually shifted from the focal plane to reveal regions of growth

structure) out to >60 days within the target area — this was anecdotal information that supported the

assumption that several months of otolith material was extracted for 14C analyses. No treatment of the

distal otolith surface (other than removal of the distal knob) was necessary because the earliest growth

remained on the upper surface, as determined from transverse sections (e.g., Fig. 1). Final extracted core

dimensions were approximately 3.5 mm long by 1.1 mm wide by 0.5 mm thick and a mean sample mass

of 0.005 g.