Behavioural
Processes,
435
11 (1985) 435-438
Elsevier Letter
THE EFFECTS OF NATE SEPARATION ON PAIR (CICHLASOMA CYANOGUTTATUM) D. MAKIE and
RE-FORMATION IN THE TEXAS CICHLID FISH
Il.ITZKOWITZ
Department of Biology, Lehigh University, Bethlehem, PA, 18015 (USA) (Accepted 8 March 851 ABSTRACT Makie D. and Itzkowitz M., 1985. The effects of mate se aration on pair re-formation in the Texas cichlid fish (Cichlasoma cvanoquPtatum). Behav. Processes 11: 435-438. This stud tested whether mated pairs of Texas cichlid tC?N;;;;; cvanosuttatumY would reform and continue rearing their offspring af er separated for either one. four. or ten days. All pairs successfully re-formed after one day, while only 50% re-formed after Irdays. No air re-formed after 10 days of separation. In successfully re-formed pairs, tKe female was always a~:;;~;:resslve than her mate! irrespective of whether the female was the e or the returning individual. Aggressiveness seemed related to the female's attempt to control the male's parental behavior. For pairs which did not re-form, the resident parent, either the male or female. violently and continuously attacked the returned mate. INTRODUCTION Many species of
he absence of the female, the male Texas cichlid (Cichlasoma much time with the offspring as does a female (Itzkowrtz, 1984). These data, as observations notin that the female aggressive1 displaces the as well male from the offspring, sugges!s that the female controls t1e male's access to the offspring. This study looks more closely at the gair bond of the Texas cichlid (Cichlasoma cvanosuttatum) by testing the a illty of mated pa+rs to ye-form after.vary+ng periods of separation. The Texas cichlid isg;o:ypical substrate In both field brooding cichlid fish (Baerends and Baerends-van Roan, (Itzkowltz and Nyby, 19821 and aquaria (Itzkowitz. 198&l the-mates of a pair select a hard surface for egg deposition and vi orously defend it and the surrounding area. Courtship behavior indicative os a pair soon to lay e gs is the quivertng of the anterior part of the body at the approach of the ma9e and ze;e;xtension of, unpaired fins !i.e.. lateral display) The scraping of the spawning site and the removal the deposition of adhesive eggs. The eggs hatch in (non-swimmerswith yolk sacs) are transferred to pre-dug The wriggler stage ends in approximate1 6 days with the appearance fry form an amorphorous SCx001 and slowly meander around the territor This final stage seems to end in 3 or 4 days under field conditions with tE. e young dispersing out of the territory. The laboratory manipulations were designed to emphasize how each sex responds to mate separation as either the resident parent or the returnee. As the,female performs more direct offspring care than the male, the sexes w;er~ anticipated to be different ln.!their ability to resume parental care. resump ion of the pair bond and arental care would appear to be dependent on two basic aspects: (1) The abili y of both parents to recognize the other fish as it's mate, and (21 the resumption of parental behavior by the returning individual. Although we know of no other which tests these points. Krischik and Weber (19751 induced parentalst%%avior in non-parenting ;;i; cichlids by repeatedly exposing them to schools of free-swimming fry. using fr Heuts B. (pers. comm.1 induced parental care in male Hemichromis l~~~culae' us that had some rior experience in raising their own offspring. some evidence exists Bhat parents may resume their parental activities afte; prolonged absences when confronted with offspring.
0376-6357/85/$03.30
0 1985 Elsevier Science
Publishers
B.V. (Biomedical
Division)
436
METHODS
The fish used in this stud were purchased from a commercial supplier. The parental behavior of these I. ish did conform to those observed under field conditions. A stock of about 150 individuals was maintained in 473 I aquaria. Experiments were conducted in 254 L tanks that had a fine sand substratum with one flower pot at one end. To form pairs, 8 to 10 fish were randomly selected from stock tanks and placed into experimental tanks. A pair usually formed within a day or two and all other fish were removed. The eggs were typically 3-~,",,~~ the flower pot. Twenty-four hours after egg deposition, one parent was The experimental procedure consisted of removing either the male or female arent. tagging it, and placing it into a stock tank. The parent was returned o it's mate and offs ring after 24 h (egg stage; N=lO). 96 h (wriggler stage; e,ElO, or 10 days Pfry stage; N=71. After mate replacement. behavioral obser;ations were taken for the first 15 min. At irregular intervals. observations were made during the next 24 h to determine the approximate time the pair began to behave normally by showing synchronized alternation of duties. RESULTS All mates (N=12), irrespective of sex (6 males and 6 females). removed and returned after 24 h did re-pair and continue to successfully rear their offsprin In contrast. only 50% (5110) pairs re-formed after mate replacement after 4 x* ays and no pair (O/71 ye-formed after being separated for 10 days. Before separation, bouts of fighting between the parents were never observed during the 24 h period after the intruders were removed, nor did it occur later in the Parental cvcle (Itzkowitz, in prep.). The separation and then re lacement of a mate produced some uncharacteristic aggression among mates t$at did re-pair. There was no apparent difference in aggression between successfully re- aired mates based on the duration of mate separation (i.e. one or four daysP and these will be combined for further analysis. Procedures for the Fisher Exact Test were taken from Siegel (1956). Successful Re-pairs When both resident and returnee females are considered together (N=171, they have a significantly longer duration of lateral displays (a threat behavior usually receeded an attack) than the combined group of males (H=171 (Fisher Exact Tese* p
Processes,
435
11 (1985) 435-438
Elsevier Letter
THE EFFECTS OF NATE SEPARATION ON PAIR (CICHLASOMA CYANOGUTTATUM) D. MAKIE and
RE-FORMATION IN THE TEXAS CICHLID FISH
Il.ITZKOWITZ
Department of Biology, Lehigh University, Bethlehem, PA, 18015 (USA) (Accepted 8 March 851 ABSTRACT Makie D. and Itzkowitz M., 1985. The effects of mate se aration on pair re-formation in the Texas cichlid fish (Cichlasoma cvanoquPtatum). Behav. Processes 11: 435-438. This stud tested whether mated pairs of Texas cichlid tC?N;;;;; cvanosuttatumY would reform and continue rearing their offspring af er separated for either one. four. or ten days. All pairs successfully re-formed after one day, while only 50% re-formed after Irdays. No air re-formed after 10 days of separation. In successfully re-formed pairs, tKe female was always a~:;;~;:resslve than her mate! irrespective of whether the female was the e or the returning individual. Aggressiveness seemed related to the female's attempt to control the male's parental behavior. For pairs which did not re-form, the resident parent, either the male or female. violently and continuously attacked the returned mate. INTRODUCTION Many species of
he absence of the female, the male Texas cichlid (Cichlasoma much time with the offspring as does a female (Itzkowrtz, 1984). These data, as observations notin that the female aggressive1 displaces the as well male from the offspring, sugges!s that the female controls t1e male's access to the offspring. This study looks more closely at the gair bond of the Texas cichlid (Cichlasoma cvanosuttatum) by testing the a illty of mated pa+rs to ye-form after.vary+ng periods of separation. The Texas cichlid isg;o:ypical substrate In both field brooding cichlid fish (Baerends and Baerends-van Roan, (Itzkowltz and Nyby, 19821 and aquaria (Itzkowitz. 198&l the-mates of a pair select a hard surface for egg deposition and vi orously defend it and the surrounding area. Courtship behavior indicative os a pair soon to lay e gs is the quivertng of the anterior part of the body at the approach of the ma9e and ze;e;xtension of, unpaired fins !i.e.. lateral display) The scraping of the spawning site and the removal the deposition of adhesive eggs. The eggs hatch in (non-swimmerswith yolk sacs) are transferred to pre-dug The wriggler stage ends in approximate1 6 days with the appearance fry form an amorphorous SCx001 and slowly meander around the territor This final stage seems to end in 3 or 4 days under field conditions with tE. e young dispersing out of the territory. The laboratory manipulations were designed to emphasize how each sex responds to mate separation as either the resident parent or the returnee. As the,female performs more direct offspring care than the male, the sexes w;er~ anticipated to be different ln.!their ability to resume parental care. resump ion of the pair bond and arental care would appear to be dependent on two basic aspects: (1) The abili y of both parents to recognize the other fish as it's mate, and (21 the resumption of parental behavior by the returning individual. Although we know of no other which tests these points. Krischik and Weber (19751 induced parentalst%%avior in non-parenting ;;i; cichlids by repeatedly exposing them to schools of free-swimming fry. using fr Heuts B. (pers. comm.1 induced parental care in male Hemichromis l~~~culae' us that had some rior experience in raising their own offspring. some evidence exists Bhat parents may resume their parental activities afte; prolonged absences when confronted with offspring.
0376-6357/85/$03.30
0 1985 Elsevier Science
Publishers
B.V. (Biomedical
Division)
436
METHODS
The fish used in this stud were purchased from a commercial supplier. The parental behavior of these I. ish did conform to those observed under field conditions. A stock of about 150 individuals was maintained in 473 I aquaria. Experiments were conducted in 254 L tanks that had a fine sand substratum with one flower pot at one end. To form pairs, 8 to 10 fish were randomly selected from stock tanks and placed into experimental tanks. A pair usually formed within a day or two and all other fish were removed. The eggs were typically 3-~,",,~~ the flower pot. Twenty-four hours after egg deposition, one parent was The experimental procedure consisted of removing either the male or female arent. tagging it, and placing it into a stock tank. The parent was returned o it's mate and offs ring after 24 h (egg stage; N=lO). 96 h (wriggler stage; e,ElO, or 10 days Pfry stage; N=71. After mate replacement. behavioral obser;ations were taken for the first 15 min. At irregular intervals. observations were made during the next 24 h to determine the approximate time the pair began to behave normally by showing synchronized alternation of duties. RESULTS All mates (N=12), irrespective of sex (6 males and 6 females). removed and returned after 24 h did re-pair and continue to successfully rear their offsprin In contrast. only 50% (5110) pairs re-formed after mate replacement after 4 x* ays and no pair (O/71 ye-formed after being separated for 10 days. Before separation, bouts of fighting between the parents were never observed during the 24 h period after the intruders were removed, nor did it occur later in the Parental cvcle (Itzkowitz, in prep.). The separation and then re lacement of a mate produced some uncharacteristic aggression among mates t$at did re-pair. There was no apparent difference in aggression between successfully re- aired mates based on the duration of mate separation (i.e. one or four daysP and these will be combined for further analysis. Procedures for the Fisher Exact Test were taken from Siegel (1956). Successful Re-pairs When both resident and returnee females are considered together (N=171, they have a significantly longer duration of lateral displays (a threat behavior usually receeded an attack) than the combined group of males (H=171 (Fisher Exact Tese* p
